&EPA
United States
Environmental Protection
Agency
EPA/600/R-13/133 July 2013 www.epa.gov/research
1980, Summer-Long Grazing
Linking Changes in Management and
Riparian Physical Functionality to
Water Quality and Aquatic Habitat
A Case Study of Maggie Creek, NV
2011, Shortened and Variable
Grazing Season Since 1994
RESEARCH AND DEVELOPMENT
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Linking Changes in Management and
Riparian Physical Functionality to
Water Quality and Aquatic Habitat:
A Case Study of Maggie Creek, NV
Prepared by
Don Kozlowski1, Sherman Swanson2, Robert Hall3, Daniel Heggem1
1U.S. Environmental Protection Agency
Office of Research and Development
National Exposure Research Laboratory
Environmental Sciences Division
Las Vegas, NV89119
Department of Natural Resources and Environmental Science
University of Nevada,
Reno, NV 89557
3
U.S. Environmental Protection Agency
Region 9 WTR2
San Francisco, CA 94105
Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect
official Agency policy. Mention of trade names and commercial products does not constitute
endorsement or recommendation for use.
U.S. Environmental Protection Agency
Office of Research and Development
Washington, DC 20460
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Table of Contents
List of Tables iv
List of Figures vi
Acronyms and Abbreviations vii
Acknowledgement 1
Abstract 3
Introduction 4
I. Proper Functioning Condition (PFC) 5
II. PFC Attributes and Water Quality 6
A. Hydrological Attributes 6
1. Floodplain Inundated in "Relatively Frequent" Events (1-3 Years) 6
2. Where Beaver Dams Are Present They Are Active and Stable 7
3. Sinuosity, Width/Depth Ratio, and Gradient are in Balance with the Landscape Setting
(i.e., "Landform, Geology, and Bioclimatic Region) 8
4. Riparian Zone is Widening or has Achieved Potential Extent 9
5. Upland Watershed not Contributing to Riparian Degradation 10
B. Vegetation Attributes 10
1. Diverse Age-Class Distribution (Recruitment for Maintenance /Recovery) 11
2. Diverse Composition of Vegetation (for Maintenance/Recovery) 11
3. Species Present Indicate Maintenance of Riparian-Wetland Soil
Moisture Characteristics 12
4. Streambank Vegetation is Comprised of Those Plants or Plant Communities that
have Root Masses Capable of Withstanding High Streamflow Events 12
5. Riparian Plants Exhibit High Vigor 13
6. Adequate Vegetation Cover Present to Protect Banks and Dissipate
Energy During High Flows 13
7. Plant Communities in the Riparian Area are an Adequate Source of
Coarse and/or Large Woody Debris 14
C. Erosion/Deposition Attributes 15
1. Floodplain and Channel Characteristics (i.e., Rocks, Overflow Channels, Coarse
and/or Large Woody Debris) Adequate to Dissipate Energy 15
2. Point Bars are Revegetating with Riparian-Wetland Vegetation 15
3. Lateral Stream Movement is Associated with Natural Sinuosity 16
4. System is Vertically Stable 16
5. Stream is in Balance with the Water and Sediment being Supplied by the Watershed
(i.e., No Excessive Erosion or Deposition) 16
Functional Rating 16
11
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Implications to Water Quality: Sediment, Nutrients, Temperature, and
Dissolved Oxygen (DO) 17
Justification 19
Objective and Hypotheses 20
Hypotheses 21
Site Description 21
History 30
Water Quality Stations 30
Water Quality Data Available 31
Methods 32
Assessing Stream Functional Condition 33
Precipitation and Discharge 33
Water Quality and Aquatic Habitat Data 34
Total Suspended Solids (TSS) 34
Orthophosphate Phosphorus (OP-P) 34
Nitrogen (Total Nitrogen (TN), Total Kjeldahl Nitrogen (TKN)
and Nitrate/Nitrite (NOx)) 34
Dissolved Oxygen (DO) 35
Water Temperature 35
Results 35
Stream Functional Conditions 35
Precipitation and Discharge 38
Total Suspended Solids (TSS) 42
Orthophosphate Phosphorus (OP-P) 47
Nitrogen: Total (TN), Total Kjeldahl (TKN), and Nitrate + Nitrite (NOx) 53
Dissolved Oxygen (DO) 55
Water Temperature 58
Discussion 58
Conclusion 64
References 66
in
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List of Tables
Table 1. Summary of Water Quality Implications for Checklist Item
Responses in PFC Assessment 17
Table 2. Percentage of Stream Miles that Changed According to Attribute 37
IV
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List of Figures
Maggie Creek with Season-Long Cattle Grazing in 1980 ...................................... Front Cover
Cover
(Top)
Cover
(Bottom) Maggie Creek in 20 1 1 with Shortened Season of Use Differing
Among Years Since 1 994 [[[ Front Cover
Figure 1. The Main Physical Impacts of Riparian Vegetation on Water Cycling ................................. 14
Figure 2. Study Area, Maggie Creek, NV [[[ 22
Figure 3. Maggie Creek, NV, River Reach and 12-Digit Hydrologic Units ......................................... 23
Figure 4. Maggie Creek, NV, BLM Grazing Allotments [[[ 24
Figure 5. Maggie Creek, NV, Land Ownership [[[ 25
Figure 6. Maggie Creek, NV, Ecoregions [[[ 26
Figure 7. Maggie Creek, NV, Land Covers [[[ 27
Figure 8. Maggie Creek, NV, Fire Event Areas [[[ 28
Figure 9 . Management Change and Water Quality Stations along Maggie Creek ............................... 31
Figure 1 0 . Water Quality Data Available at USGS Gage Station 10321950
onHydrograph [[[ 32
Figure 11. PFC Stream Reaches Assessed Along Maggie Creek [[[ 35
Figure 12. Yearly Precipitation in Elko, NV [[[ 38
Figure 13. Monthly Precipitation at Elko, NV vs. Daily Hydrograph of
Maggie Creek [[[ 39
Figure 14. Comparison of Upstream (Bold Line) and Downstream (Light Line)
Gage Stations on Maggie Creek [[[ 40
Figure 15. Cumulative Frequency Distribution of Discharge at
Maggie Creek, 1990-2006 [[[ 41
Figure 16. TSS Trend at Upper Station, Pre- and Post-Management Change ........................................ 42
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Figure 26. Median OP-P Concentrations and Flows at Upper and Lower
Stations Based on Two-year Intervals 52
Figure 27. Nitrogen Concentration Trends at the Lower Station 53
Figure 28. TKN Concentration Trends at Upper and Lower Stations 54
Figure 29. DO Concentration Trend at Lower Station,
Pre- and Post-Management Change 55
Figure 30. DO Concentration Trend at the Upper Station,
Pre- and Post-Management Change 56
Figure 31. Yearly Average Air Temperature Trend at Elko, NV, 1990-2006 57
Figure 32. Yearly Average Water Temperature Trend at Upper and Lower Stations 58
vn
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Acronyms and Abbreviations
AMD Acid Mine Discharge
BLM Bureau of Land Management
B&W Black and White
C Celsius
CIR Color Infrared
DO Dissolved Oxygen
DOQQs Digital Orthophoto Quarter-Quadrangles
DP Dissolved Phosphorus
EPA Environmental Protection Agency
FAR Functional At Risk
GIS Geographic Information System
GPS Global Positioning System
ID Interdisciplinary Team
LCT Lahontan Cutthroat Trout
MCWRP Maggie Creek Watershed Restoration Project
N Nitrogen
NAIP National Agriculture Imagery Program
NaOH-P Sodium Hydroxide Extractable Phosphorus
NDEP Nevada Department of Environmental Protection
NF Non-functional
NHD National Hydrologic Dataset
NH4-N Ammonia Nitrate
NOAA National Oceanic and Atmospheric Administration
NO3-N Nitrate Nitrogen
Vlll
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Acronyms and Abbreviations (cont.)
NOx Nitrate/Nitrite
NWIS National Water Information System
OP Ortho-Phosphate
OP-P Orthophosphate Phosphorus
P Phosphorus
pH Hydrogen Ion Concentration
PFC Proper Functioning Condition
PP Particulate Phosphorus
Q Stream Flow
SOAP South Operations Area Project
TKN Total Kjeldahl Nitrogen
TMDL Total Maximum Daily Load
TN Total Nitrogen
TP Total Phosphorus
TSS Total Suspended Solids
USEPA United States Environmental Protection Agency
USFS United States Forest Service
USGS United States Geological Survey
VLSA Very Large Scale Aerial
WQ&AH Water Quality and Aquatic Habitat
IX
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Acknowledgement
This study was funded by the USEPA. Special thanks to Carol Evans, Bureau of Land Management
(BLM) Elko fisheries biologist, for providing support.
Special thanks also to the Newmont Mining Corp. for helping to improve riparian conditions along
Maggie Creek by the recognition of non-functional systems and the demonstration of good land
stewardship through cooperation with numerous stakeholders. We also thank these parties for providing
open access to water quality data they have collected. We are also grateful to those who help us with this
report in their time and effort including, David Bradford and Kent McAdoo (reviewers), Maria Gregorio,
Kuen Huang-Farmer, Tad Harris and Pamela Grossmann.
Notice
The information in this document has been funded in part by the United States Environmental
Protection Agency under Student Services Contract number EP09D000249 to Don Kozlowski.
It has been subjected to the Agency's peer and administrative review and has been approved for
publication as an EPA document.
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Abstract
The total maximum daily load (TMDL) process is ineffective and inappropriate for improving stream
water quality in the rural areas of the northern Great Basin, and likely in many areas throughout the
country. Important pollutants (e.g., sediment and nutrients) come from the stream systems rather than
external point or nonpoint sources where TMDL focuses. Water quality indicators lag behind ecosystem
functions, and monitoring water quality fails to identify causes of, or recovery from, loss offish habitat,
the most sensitive beneficial use. Ambient monitoring programs should identify risk and recovery,
focusing resources toward effective land and water management strategies. To illustrate, we elucidate the
connections between various water quality attributes and the seventeen items of the interagency riparian
proper functioning condition (PFC) assessment for lotic (running water) riparian systems. We conducted
PFC assessment for relevant parts of the Maggie Creek Watershed, and developed hypotheses of
improved water quality from improved management and riparian conditions. We then tested these
hypotheses using a far more intensive water quality monitoring data set than is generally available to
either rangeland or water quality managers. The Maggie Creek, NV, case study demonstrates that
changes in grazing management (timing and duration) resulted in improved stream functionality, leading
to reduced sediment and phosphate, increased dissolved oxygen, and improved aquatic habitat. It also
demonstrates that monitoring for water quality by monitoring water chemistry requires unaffordable
frequency and generates highly variable data that obscures relevant issues while it fails to monitor drivers
of system collapse or recovery. Thus water chemistry monitoring fails to timely inform management of
impairment risk or the trend from management actions. We suggest that published protocols for
monitoring multiple indicators of riparian functions are more relevant, faster, and less expensive.
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Introduction
Streams differ in their potential to produce habitats, biota, and water quality for beneficial uses. Stream
differences are often discussed or classified using stream order (Strahler 1964), valley confinement and
landform setting, gradient, substrate, entrenchment, width/depth ratio, sinuosity, and bed form (e.g.,
Rosgen 1996, 2006, Knightonl998). Differences are caused by climate and geologic parent material, as
well as historic and prehistoric human modifications (Dunne and Leopold 1978, Mann 2005). Riparian
vegetation exerts strong influences on channel form and ecological processes (Prichard et al. 1998). The
importance of riparian vegetation and its differing roles in various geomorphic and ecological settings has
led to numerous riparian vegetation classifications (e.g., Manning and Padgett 1995) and scorecards (e.g.,
Weixelman et al. 1996).
Maintaining healthy aquatic and riparian habitats depends on management that allows or facilitates
natural recovery of riparian functions after natural or anthropogenic disturbance. These functions include
dissipating flood energy and slowing travel rates of materials out of their watershed positions; erosion and
deposition of sediment to maintain floodplain access and channel pattern, profile, and dimension
appropriate for the landform setting; hydrologic processes of aquifer recharge and hyporheic interchange;
and growth and reproduction of stabilizing plant communities. Maintaining these dynamic functions
provides riparian floodplain and aquatic capital that create extremely productive fish and wildlife habitats
and soils, high water quality, high biodiversity, and other ecosystem services. Impairment of riparian
functions changes hydrologic, vegetative, and geomorphic interrelationships and may trigger cascading
effects.
When management goes awry with nature or up- or down-stream neighbors exceed boundaries of
dynamic equilibrium with too much or too little sediment or water or by changing vegetation or base
level, it is not uncommon for streams to incise. This sets in motion a long-term chain reaction of
geomorphic adjustment that leads to significant changes in water quality and aquatic habitats.
Anthropogenically altered water cycles often lead to hydrologic alterations such as increased/decreased
volume and velocity of runoff and size and frequency of floods, altered groundwater discharge, and
changes in runoff storage capacity in wetlands, soil, and aquifers. Alterations frequently create additional
environmental stressors via erosional/depositional processes such as changes in sediment and chemical
concentrations (often considered pollutants) in the water. These changes modify habitats and affect other
beneficial uses of water or water bodies. To address the aquatic impacts from environmental stressors, it
is important to understand the interconnectivities of a system and recognize the fundamental changes to
riparian ecosystem services coming from changes in hydrology, vegetation, and soil erosion/deposition
within a geomorphologic context.
Properly functioning streams and riparian systems provide a steadying influence on various water quality
and aquatic habitat attributes. Riparian proper functioning condition assessment connects to water quality
and aquatic habitat by assessing the degree of functionality and the risk of losing this functionality. The
job of a stream is to transport water and sediment; the key question is always the rate of that transport.
Functioning streams dissipate the energy of flowing water. Stream potential energy, represented by
higher elevation water influenced by gravity, has the power to exceed the critical shear stress of soil,
banks, bed, or floodplains as it changes to kinetic energy. Dissipated energy is less likely, at any one
spot, to exceed the critical shear stress of that material and cause erosion. Similarly, when water slows, it
may no longer provide the velocity and turbulence to keep particles suspended or moving, leading to
deposition.
Sediment is a major pollutant across the nation (USEPA 2009). Reducing erosion, or inducing
sedimentation, has direct water quality implications. Sediment is the primary medium for transporting
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organic/inorganic chemicals that impact aquatic biota and beneficial uses (e.g., recreation and wildlife).
Pathogens and nutrients are the most common biological and chemical stressors to wildland streams and
lentic wetlands. Excess nutrients cause eutrophication. Ideally, the rate of nutrient availability should
remain reasonably steady at an appropriate level for the community of organisms of the system to
function. The appropriate level and variability differs widely among locations and stream reaches.
Temperature and other environmental variables fluctuate through time and space in relation to diurnal and
annual cycles. Aquatic organisms alter their individual physiology and community structure to adapt to
the respective systems' normal range of variation (Barnes and Minshall 1983). Properly functioning
streams vary the magnitude of the fluctuations within a narrower range. Thus, temperature dependent
biological and chemical processes operate with lower variation. Well vegetated and functioning stream
and wetland systems typically decrease aquatic insolation and reduce heat exchange through radiation.
They ameliorate fluctuations of water volume (downstream low flows and floods) through underground
storage with aquifer recharge and hyporheic interchange. Thus, winter low temperatures remain higher
and summer high temperatures remain lower.
Riparian Proper Functioning Condition (PFC) assessment (Prichard et al. 1998) connects to water quality
through system attributes that collectively lead managers to grasp the story of individual reaches and the
overall watershed. This study assesses changes in riparian physical functionality and biophysical
alterations due to changes in land management strategies. Understanding the resulting changes in water
quality and aquatic habitat at a local scale empowers resource managers for adaptive management
alternatives using the PFC protocol.
PFC
PFC is an interagency assessment protocol focusing on physical structure and functioning in relation to
on-site potential. Although qualitative, it is based upon quantitative science (e.g. Prichard et al. 1998
(from Leonard et al. 1992) and incorporates the important attributes that numerically based surveys
commonly address. An interdisciplinary team conducting PFC assessment in the field uses all relevant
science and life experience to inform understanding of local potential, what is locally possible, and what
is needed for the system to maintain functions in large flow events. This avoids a similar process of
interpretation of quantitative survey data in the office based on standard expectations or classifications
that only partially capture inherent spatial variability in potential and attributes needed for ecosystem
functions. A PFC rating relates how well the physical stream processes are functioning. To be properly
functioning, a riparian system will: "Dissipate stream energy associated with high water flows, thereby
reducing erosion and improving water quality; filter sediment, capture bedload, and aid floodplain
development; improve floodwater retention and groundwater recharge; develop root masses that stabilize
streambanks against cutting action; develop diverse ponding and channel characteristics to provide the
habitat and the water depth, duration, and temperature necessary for fish production, waterfowl breeding,
and other uses, and; support greater biodiversity."
To determine how well a riparian area functions to achieve these criteria, an interdisciplinary team of
experienced professionals uses a checklist of seventeen attributes in three categories: hydrology,
vegetation, and erosion/deposition. The functional attributes in the PFC checklist provide important foci
for this study's research. The rationale for the PFC assessment, including all seventeen attributes, has
been summarized in technical references (Prichard et al. 1993 (revised and elaborated by Prichard et al.
1998).
When the stream and riparian system functions properly, meeting the previously mentioned criteria, it will
be stable and resilient to major hydrologic events, even those with recurrence intervals of at least 25-30
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years (Prichard et al. 1998). Stream stability requires that a stream be self-sustaining, retain the same
general geometry over time (decades), and balance the import and export of sediment (Ward and Trimble
2004). These generalizations come from studies of a multitude of streams in various locales. Miller et al.
(2004) describe a Great Basin morphologic setting influenced by climate changes that implies some
riparian systems in this region may be more sensitive to disturbance and incision than "typical" streams.
The hydrologic/stability interval expressed by Prichard et al. (1998) suggests possible instability at lower
probability/higher magnitude events. Yet PFC streams may buffer the hydrologic and geomorphic
stresses of even dam-break events analogous to extremely rare precipitation events. Prichard et al. (1993
and 1998) also describe mechanisms of natural recovery toward a renewed stability with restored
functionality borrowing from Jenson et al. (1989) and many others.
If a riparian area does not function properly, it may not retain the same general geometry overtime and
may be out of balance regarding sediment transport. If the riparian zone is functioning but stressed or "at
risk" because one or more attributes makes it susceptible to degradation, it may be prone to excess
channel changes during major disturbances such as flooding or fire. These alter water levels and plant
growing conditions, degrade nutrient uptake, and accelerate erosion. Undissipated hydraulic energy
detaches particles ineffectively bound by roots. Kozlowski (2007) modeled changes in several stream
channel attributes of burned northern Nevada riparian zones using PFC attributes, functional ratings,
precipitation, and upland and riparian burn severity.
PFC Attributes and Water Quality
Each item of the PFC assessment addresses a specific and important attribute or process necessary to
maintain a functioning riparian system. Similarly, each plays a role in maintaining good water quality,
especially for those parameters of most concern in the rural streams of the northern Great Basin:
baseflow, sediment, nutrients, dissolved oxygen, and water temperature. These important attributes
commonly focus water quality managers for wildland streams wherever rangeland, forestry, or recreation
management predominates. Furthermore, this conceptual foundation supports water quality management
for management settings where pollution inputs outside of riparian areas dominate.
A) Hydrologic Attributes
1 - Floodplain Inundated in "Relatively Frequent" Events (1-3 Years).
The active floodplain (Gebhardt et al. 1989) is the area next to the stream where inundation occurs when
bankfull discharge is exceeded, which occurs on average about two out of three years (Leopold 1994).
Where a stream has frequent access to its floodplain, the energy associated with flood flows can be
dissipated in shallow water across a wide surface and by the friction provided by riparian/floodplain
vegetation with multiple stems. Shallow depth and roughness slows the velocity, allowing excess
sediment to deposit rather than move downstream where it could damage economies and aquatic species
habitats from algae to fish (Bilotta and Brazier 2008). Spreading and infiltrating water across a broad
surface recharges aquifers. Saturation and availability of soil moisture then interacts with soils, climate,
and management to control the distribution of plant communities. Species associations, their niche within
the floodplain, and the internal structure of riparian communities are closely link to flood duration,
frequency, and stream energy. An important edaphic and climatic variable, soil moisture is a major
determining factor in the establishment and survival of herbaceous and woody plants (Girel and Pautou
1997). Infiltrated water and the sediment deposited on the floodplain may be laden with pollutants or
nutrients which can then be taken up in plants and incorporated into a food web, slowing their
downstream spiral. Water infiltrated and percolated down to the water table recharges aquifers and
extends baseflow into dry seasons or years. Ground water discharge helps stabilize flow and moderate
the water temperature of streams (Caissie 1991; Blackport etal. 1995). Baseflow is often the result of
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ground water discharge into streams (Freeze and Cherry 1979; Blackport et al. 1995). Cooler water in
discharge zones during summer allows for higher dissolved oxygen (Caissie 1991; Power et al. 1999),
while relatively warmer water temperatures from discharge zones during the winter often keep water from
freezing into the bed (anchor ice) and occupying refugia habitats (Cunjak and Power 1986; Power et al.
1999). Internal structure of riparian plant communities is linked to topography and flooding frequency,
resulting in biodiversity changing along a gradient of elevation (Girel and Pautou 1997; Bush and Van
Auken 1984; Hupp and Osterkamp 1985). Frequent flooding and the associated anoxic soil conditions
are often needed to sustain riparian vegetation (Girel and Pautou 1997; Kozlowski 1984), especially the
stabilizing wetland plants needed for channel stability (see items 8 and 9). The roughness encountered
during energy dissipation coupled with the increase in water surface area may lead to increases in
dissolved oxygen during flood events. Energy dissipation during floods allows streambank vegetation to
withstand flood forces to narrow and shade channels, decrease insolation and summer temperatures, and
increase dissolved oxygen.
Denitrification and sediment phosphorous adsorption are strongly influenced by water residence duration
and accumulation of fine textured organic rich sediment. Management activities that maintain flooding
and increase these processes increase the buffering capacity for nitrogen and phosphorous (Hill 1997).
Spatial and temporal retention of nutrients are linked to geomorphology of catchments and channels
(Marti and Sabater 1996). Reducing conditions that change pH values and mobilize minerals such as
phosphorous, nitrogen, and magnesium occur during periods of anoxia. Repeated flooding and draining
favors denitrification (Girel and Pautou 1997). Van Vliet and Zwolsman (2008) found that decreases in
discharge due to drought brought on increased water temperatures, nutrient loads, and algal blooms.
Kaushal et al. (2008) demonstrated increased geomorphic stability and increased denitrification by
restoring and reconnecting an urban floodplain. Where or when a stream incises, it loses the important
function of floodplain inundation and the water quality benefits associated with it. Streambanks then
accelerate erosion and become pollution sources.
2 - Where Beaver Dams are Present they are Active and Stable.
Where dams are present, many implications for water quality depend on whether they are active and
stable. If a dam is not being maintained or cannot be maintained long-term due to limitations of beaver
forage or woody building material, it is inactive or unstable. Loss of a dam means potential degradation
and adjustment that can include stream incision, loss of floodplain access, riparian dehydration, channel
widening, and lateral migration. A dam's ability to hold up against storm flows depends on the dam's
condition, which is controlled by factors such as beaver food availability, predation on beaver,
abandonment, or the tunneling of other animals into and around the dam. Catastrophic failure of a dam
can lead to rapid downcutting through accumulated sediment. Implications to water quality are then
similar to those addressed in attribute 3.
Demmer and Beschta (2008) found that beavers facilitate riparian recovery. With increased beaver
activity, dams/ponds accumulated sediment, improved conditions for establishment and growth of
riparian plants, and altered channels, making them more complex from the formation of new meanders,
pools, and riffles. Accumulated sediments provided fresh seedbeds for regeneration of various riparian
plants where breaches occurred. Altered wetness further adjusted plant communities. Where beavers
abandoned reaches due to heavy utilization of riparian vegetation, eventually woody vegetation occupied
a larger portion of the floodplain. Wright et al. (2002) show that by increasing habitat heterogeneity via
beaver dams, the number of herbaceous plant species increased by 33%, thereby increasing species
richness on a landscape scale. This links directly to the importance of diverse composition of vegetation
needed for channel maintenance and recovery (attribute 7, Table 1).
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Klotz (2010), summarizing literature and using empirical data, found a 35.5% reduction of nitrate levels
of water passing through beaver ponds. Reduction was greater during warmer periods, suggesting
biological processes were responsible. Nitrates may have been transformed with microbial denitrification
enhanced by anoxic substrates, ample organic matter, and increased residence times. Burchsted et al.
(2010) describe increased area of combined surface water and elevated groundwater table across beaver
impoundments. Longitudinal sediment transport is discontinuous as impoundments store fine grained and
organic sediment. Deposition creates riparian landforms that can persist for centuries to millennia,
created by a net balance of sediment accumulation and typically leading to a reducing environment and
denitrification. Oxygen is depleted within the impoundment water column and sediments due to slow
water and high productivity. Anoxic conditions create a net storage of organic nitrogen. Relatively
higher levels of nitrogen may come out of an impoundment if levels were low going in due to increased
microbial activity and beaver's addition of organic matter. However, if levels are high going in there can
be a net decrease in transport out. Maret et al. (1987) found that during high flows (spring runoff), total
suspended solids (TSS), total phosphorus (TP), sodium hydroxide extractable phosphorus (NaOH-P), and
total kjeldahl nitrogen (TKN) were reduced when flowing through a series of beaver ponds. During low
flow the ponds had less of an effect. Nitrate nitrogen (NO3-N) was reduced in both high and low flows.
Ortho-Phosphate (OP) did not appear to be affected by the ponds. Ammonia nitrate (NH4-N) was always
quite low.
The primary source of NaOH-P was from the TSS. TSS explained a large portion of TP and TKN. TP
and OP were often significantly correlated. Bank and channel erosion appear to be contributing sources,
and export of nutrients from banks within beaver dam areas was calculated to be less than from above or
below the ponds. There was a 50-75% reduction in TSS, 20-65% reduction in TP and TKN, and 20-25%
reduction in NO3-N within complexes as opposed to above or below them. Maret et al. (1987), Correll et
al. (2000) found beaver ponds reduced annual discharge of water (8%), TN (18%), TP (21%), and TSS
(27%). Prior to pond building all were highly significantly correlated w/discharge, but had no
relationship after six years. Nitrate and ammonium were correlated with discharge at both times.
Margolis et al. (2001) measured stream water chemistry above and below two Appalachian stream beaver
ponds and found that significant differences in chemistry were generally confined to summer. Both
impoundments increased acid neutralizing capacity and pH by acting as sinks for nitrate and ammonium.
Naiman et al. (1994) found that in beaver impoundments only a portion of nutrient and other stocks go
downstream or to the atmosphere. Much of the nutrient load is retained in the organic soil horizons that
make up the ponds. These remain available to plant communities long (decades to centuries) after beaver
meadows have been abandoned. Ultimately they help determine what communities will establish.
Ponds usually have higher summer water temperatures, but are typically found to improve cool-water
fisheries at the network scale. Due to surface water storage and ground water recharge, baseflows
generally increase, drought duration and frequency is reduced, and the duration but not the magnitude of
high flows increase. However, evapotranspiration may be important enough in some systems to reduce
baseflows. An increase in cool groundwater return to the channel can also help to mitigate the higher
temperatures.
3 - Sinuosity, Width/Depth Ratio, and Gradient are in Balance with the Landscape Setting (i.e.,
Landform, Geology, and Bioclimatic Region.
Streams in different locations differ in their gradient and form depending on their landscape setting. Steep
headwater reaches tend to be sources of water and sediment. Below these, transport reaches with lower
gradient and gently sloping margins move sediment to response reaches, where the valley widens and
where the swinging and sweeping of meanders builds a floodplain. Floodplains act in concert with the
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channel form to keep hydraulic stresses within an acceptable range that allows channel migration. Point
bars slowly build into replacement floodplain, storing sediment and nutrients, as the channel migrates.
Alluvial aquifers store water rapidly during floodplain flooding.
Erosion from focused hydraulic stress (see attributes 1 and 13, Table 1) or an imbalance of sediment and
water (see attribute 17, Table 1) may exceed a geomorphic threshold, causing incision and a long process
of incised channel evolution. This vastly increases the rate of bank erosion with channel widening,
especially through floodplain stored alluvium. Eventually, after large volumes of soil have been washed
downstream, the incision becomes wide enough to distribute stream power and begin capturing sediment
at a lower level. Later, deposition and recovery processes bring back balance to the stream (Leopold et al.
1964; Schuum 1979, Schumm et al. 1984; Gebhardt et al. (1990); Rosgen 1996, 2006; Prichard et al.
1998.
Bank erosion and sediment issues may lead to other water quality problems associated with nutrients in
freshly eroded sediment or the physical effects of sediment. Higher width/depth ratios can increase
insolation and radiation, leading to greater fluctuation in water temperatures and possibly dissolved
oxygen depletion or anchor ice. Greater width and/or increased sediment may allow deposition of fine
sediments in stream substrate. Sometimes this embeddedness limits spawning-gravel dissolved oxygen
and hyporheic groundwater/surface water interactions with implications for temperature moderation.
Channel incision and embeddedness decrease riparian plant growth and nutrient uptake. Too much
sediment is an obvious water quality problem, but so is too little. A lack of sediment (such as below
impoundments) can degrade habitat for sediment dependent organisms and change channel form due to
excess bottom scour (see attribute 17, Table 1). Stream incision generally decreases riparian amelioration
of water quality. Where stream pattern, profile, and dimension conform more closely to what is
appropriate in a given geomorphic position within a balanced system, the more natural configuration
tends to process pollutants better (Sweeney et al. 2004) at more appropriate rates and times.
4 - Riparian Zone Is Widening or has Achieved Potential Extent.
The width of stream riparian vegetation depends on the overall width of vadose water within the root
zone. A riparian zone achieves its potential aerial extent in two ways. First, there is a limit to the amount
of overall width of the zone, which is usually determined by topography, hydrology, and water table
elevation. Riparian vegetation can established itself to these outer limits. Second, riparian vegetation can
establish itself on soils deposited along the stream banks, essentially narrowing the stream, helping it
achieve equilibrium width to depth ratio. When this potential extent is achieved, the riparian zone is at its
maximum potential width to filter or buffer against various waterborne pollutants, etc. Where this occurs
there would be no expected potential for future water quality improvement due to this physical condition.
However, riparian vegetation amelioration of water quality diminishes in degraded stream systems. In a
riparian zone recovering from degradation condition, the riparian zone may have the opportunity to widen
and improve water quality.
Mayer et al. (2005) found wider riparian buffers were generally better at removing nitrogen from surface
waters and narrow buffers at times increase nitrogen delivery, but width or vegetation type was not
important to subsurface removal, which is generally efficient. Infiltration is one of the most significant
pollutant removal mechanisms. It allows for finer sediment particles (clays) to be incorporated into the
soil profile and for deposition of silt-sized and greater particles. Vegetation helps filter larger sized
particles, reduces surface runoff and thus sediment transport capacity (Dillaha and Inamdar 1997).
Widening is generally associated with increased water elevation or with building a floodplain through
channel narrowing (analogous to 1, 2 and 3 above).
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As described by Cooper et al. 1987, riparian buffer zones removed 84-90% of sediment eroded from
cropland. Much longer lengths of buffer are needed to filter incrementally more sediment (Castelle et al.
1994) e.g., doubling of buffer width is necessary to reduce sediment from 90 to 95% on 2% slopes.
Buffer strips are the most important factor in reducing sediment loads to receiving waters, with
efficiencies to 90% commonly reported in forested coastal plains (Gilliam 1994; Lowrance et al. 1995).
Buffer zones are particularly effective in low order streams, but this is reduced as stream order increases
(Lowrance et al. 1995).
Jordan et al. (1993) found that buffer zones can be sediment sources. The sink can be so great as to
"starve" the stream, creating more stream energy that works on the banks and bottom, releasing through
bank erosion wetland and/or channel soils with higher nutrient and organic content.
5 - Upland Watershed not Contributing to Riparian Degradation.
This attribute addresses whether unnatural disturbances or changes in the upland parts of the watershed
contribute to degradation of the riparian reach being assessed. Excessive sediment delivery to the stream
channel, a lack of sediment, or too much or too little water can lead to changes in the floodplain access,
sinuosity, width/depth ratio, and gradient, all stream properties and implications addressed in attribute 3,
Table 1. Implications addressed for that attribute can be expected here as well.
The main direct implication to water quality within this context is an increase in sediment load and the
associated pollutants that come along with it. These pollutants can include nearly anything, depending on
what is occurring within the watershed. Based on the nature of the sediment and the speed of its delivery,
the introduction of sediment could lead to a total loss of physical functionality of the stream reach and
thus the water quality implications of other attributes. A we 11-functioning riparian zone tends to be
resilient, handling some increases and decreases of sediment without exceeding a threshold of stability.
Therefore the issue is not simply whether the watershed has changed its delivery of water or sediment, but
rather a watershed change contributing to riparian degradation and loss of functions.
B) Vegetation Attributes
1 - Diverse Age-Class Distribution (Recruitment for Maintenance/Recovery).
A diverse age-class of riparian wetland plants, particularly woody species, is an indicator of stable
populations and is necessary for the long term maintenance of the plant community. Where age-classes
are not diverse, it is important to determine whether the populations are expanding or diminishing
(Kormondy 1969). Well established older mature plants have developed root masses capable of holding
the soil in place, and usually assure water can be obtained even in drought years. They also represent a
considerable carbon and nutrient sink. However, older communities will eventually become decadent,
more prone to disease, and in some cases create stores of dead wood that can fuel wildfires. Middle-aged
plants are necessary to take the place of older ones when they eventually die. They also lend some
resiliency to communities by being less susceptible to disease and fire while still being able to reach water
tables during drought periods. Young plants are needed to assure recruitment into the community to
perpetuate it.
Young and middle aged plants are important for recovery and maintenance of the community (Prichard
1998). Because of the increased growth rate of younger plants, they may be more efficient at assimilating
nutrients, but are more susceptible to die-off in drought situations because their root systems may not
have grown deep enough to reach water tables. However, the root systems often help stabilize soils in
shallower depth to water table zones at the streambank edge and point bars. The root systems help to
maintain riparian width and thus are important to pollutant issues associated with attribute 4, Table 1.
10
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Recruitment in and near the stream allows for increased shading and evapotranspiration, which can lead
to decreases in water temperature while increasing (DO) due to decreasing temperature and direct
contribution of oxygen by the young plants' roots. Shading may be an effective tool for the management
of algal growth (Ghermandi et al. 2009). The differing stem diameters and clustering of the different age
classes (Myers 1989) may help in trapping different size sediment particles during flood events. Missing
age classes, especially young ones, suggest altered hydrology, channel form, or management with
implications for other attributes.
2- Diverse Composition of Vegetation (for Maintenance/Recovery).
From a functionality standpoint, diverse composition of vegetation reduces the risk that an environmental
stressor for one species will diminish stability from vegetation needed when catastrophic events occur.
Diverse composition assures there will be some species more resilient to a stressor than others. Stabilizing
vegetation will help hold the stream banks and floodplain together and begin recovery.
The implication to water quality is that accelerated erosion will be held in check, reducing sediment and
its associated pollutants. Plants will be available to help mitigate nutrient loads, provide shade for
cooling, and deliver (DO) to the water. Riparian composition is affected by mechanical injury, fine
sediment deposition, inundation during flood events (Girel and Pautou 1997: Broadfoot and Williston
1973), fire, plant diseases and parasites, shading, nutrient availability, and plant succession.
Benefits outside the context of catastrophic events are numerous. Different plants have different abilities
to uptake/process nutrients, mitigate pollutants, bind soil to reduce erosion, and trap sediment. Riparian
vegetation trapping sediment and associated nutrient content from both overland flow to the stream and
stream water overflow to the floodplain has been well documented (Correll 1997). The stems, leaves, and
leaf litter of plants create the friction necessary to reduce water velocities and allow particulates to fall
out. In surface runoff, most N is in the form of organic nitrogen associated with suspended solids. Grass
is more effective at trapping particulates from overland flow (Parsons et al. 1994; Osborne and Kovacic
1993). Vegetation structure is influenced by the quality and quantity of litter from high primary
productivity within the riparian buffer (Girel and Pautou 1997). The microbes on plants and soil as well
as plant roots near the surface are able to assimilate dissolved nutrients in the water (Peterjohn and Correll
1984).
Although poplar (Populus spp) forests may be more effective than grass in the winter (Haycock and Pinay
1993), both herbaceous and woody vegetation can be very effective at removing nitrate from groundwater
(Haycock and Burt 1993). Some forests may be more effective than grass at nitrate removal (Gilliam et
al. 1997) but less effective at phosphate removal from groundwater (Osborne and Kovacic 1993). Other
studies found similar nitrate removal efficiencies between the two (Correll et al. 1996). Denitrification
potential is higher in grassed soils than forested (Groffman et al. 1991), while a combination of grass and
trees may be best (Welsch 1991). Riparian vegetation is necessary to provide organic matter to soils
necessary for denitrification (Correll 1997) and food web processes. Grass is very effective at removing
it (more effective than forests), but less effective at removing soluble inorganic nitrogen (N). Trees are
more effective at removing nitrate in groundwater.
Phosphorus (P) assimilation varies by plant species. Uusi-Kamppa et al. (1997) found dense, native
vegetation of high species diversity and deep-rooted plants promotes trapping of P in plants. Trees are
important sinks (Peterjohn and Correll 1984), and native herbs take up more P than grass (Uusi-Kamppa
and Ylaranta 1996). Vegetation can be a source or sink, depending on decay or growth. Vegetation
removes particulate phosphorous (PP) via deposition of suspended particles, dissolved phosphorous (DP)
through sorption by soil components, and biological (microbes, plants) uptake. Release of DP may occur
11
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during runoff due to release by decaying material. Rooted macrophytes pump P from sediment and
release in dissolved form (Uusi-Kamppa et al. 1997). Efficiency of riparian vegetation strips at removing
P depends on amounts of P already there, residence/contact time, kinetic factors, and temperature.
Sorption depends on aluminum and iron oxides, organic matter, and calcium carbonate, while desorption
depends on P saturation on oxide surfaces (Uusi-Kamppa et al. 1997). Riparian buffers retain more PP
than DP (Uusi-Kamppa et al. 1997). P is usually more mobile in surface runoff than subsurface flows.
Alder and willow bushes are most effective at P removal (e.g., a ten meter wide strip can mitigate nearly
100% of incoming P (Mander et al. 1991)). Retention of DP is often low, especially when the system
becomes saturated with P. Wetlands may convert PP to OP due to leaching of decaying vegetation and
high water levels, inducing anaerobic conditions and increasing solubility of phosphate (Uusi-Kamppa et
al. 1997).
3- Species Present Indicate Maintenance of Riparian-wetland Soil Moisture Characteristics.
The presence of obligate or facultative wetland species (Reed 1988) usually indicates the water table is
high enough to maintain a riparian-wetland community, especially where herbaceous and/or young
woody species occur. Most of these species have root masses that effectively bind soil (see attribute 9,
Table 1) and have roles in denitrification and other nutrient cycling. By definition, these plants
(hydrophytes) grow in wet places where other plants usually cannot, including streambanks, point bars,
mid-channel bars, and sometimes stream channel bottoms, thus making hydrophytic plants the most
important species for stream stabilization and maintenance of riparian width. They are also essential for
helping to provide shade for cooling water temperature and adding oxygen to water. Riparian vegetation
reduces solar heating through shading in low order streams (Brown and Krygier 1970) and cooling via
evapotranspiration (Beschta 1984; Theuer etal. 1984; Sinokrotand Stefan 1993). Evapotranspiration
cooling is greatest in forest environments due to high leaf area index that leads to higher
evapotranspiration rates (Peterjohn and Correll 1986).
Obligate or facultative wetland species typically have more root length and mass than other upland
species (Manning et al. 1989). Vegetation channel stability ratings for riparian community types have
been expressed by Winward (2000) and by Burton et al. (2011) and at http://rmsmim.com/. As Winward
(2000) pointed out, the "latter successional" community types are the ones expected in wetter conditions
on the greenline, and these have higher stability ratings. Presence of riparian buffers is the most
important factor controlling entry of non-point source nitrate in surface water (Lowrance et al. 1995).
4 - Streambank Vegetation is Comprised of those Plants or Plant Communities that have Root
Masses Capable of Withstanding High Streamflow Events.
An important distinction for this attribute is that streambank (the area between bankfull depth and stream
bottom) vegetation has to be comprised of obligate or facultative wetland species of a stabilizing nature.
In dry climates, the upper banks of incised channels rarely stabilize with strongly rooted hydrophyllic
vegetation unless watered from groundwater. Erosion of high banks (above frequent flows) then allows
formation of new floodplains that enable and grow from active channel streambank revegetation. Most of
these plants have root masses capable of withstanding high streamflow events (Prichard et al. 1998;
Winward 2000; Burton et al., 2011). The streambank is where most erosive, high velocity flows contact
material that is easily eroded if not stabilized, especially in the upper strata of the water column where
plant roots are strongest and most dense. Where these plants minimize bank erosion they reduce sediment
and nutrient delivery. Where weakly rooted streambank vegetation or bare banks allow erosion, most or
all sediment is delivered directly into the stream, resulting in a sediment delivery ratio much greater than
from upland erosion. Streambank plants also take up other in-stream nutrients, support oxygen in the
water, and cool the water by maintaining a narrow and deep channel and/or by providing shade. Where
these plants do not dominate, streambanks more often undercut and collapse during high flows. This can
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change the geometry of the stream (e.g., broad and shallow), leading to problems associated with attribute
3, Table 1. Riparian plant communities of Nevada were classified by Weixelman et al. (1996), Manning
and Padget (1995), and the United States Forest Service (USFS 1992). Winward (2000) evaluated rooting
depth, density, and toughness of named riparian plant communities on a 1-10 rating scale. Individual
species were similarly rated for their bank stabilizing effects by Burton et al. (2011). When wetland
plants have the additional benefit of growing on an accessible floodplain, the combination of floodplain
energy dissipation and floodplain aquifer recharge to support hydrophilic plants make streambanks
especially stable. Whereas loss of floodplain functions (see attribute 1) tends to diminish attributes 8, 9,
and 10, Table 1.
5 - Riparian Plants Exhibit High Vigor.
Plants exhibiting high vigor indicate good health with strong reproduction and rooting systems that bind
soil and reduce erosion. New propagules are available to colonize new sediment deposits and areas bared
by floods. Leaves and stems are larger and more effective at trapping particulates as flood waters flow
across them and also provide for more shading and ameliorated water temperatures. Two major processes
responsible for nitrate removal are plant uptake and denitrification (Gilliam et al., 1997). Numerous
studies relate the removal of nitrate to riparian buffers (Hill 1997) (see attribute 7, Table 1). Rapidly
growing plants process more nutrients. Also, vigorous riparian plants may indicate that nutrients are
effectively being removed. Measures of plant vigor often focus on root systems.
6 - Adequate Vegetation Cover Present to Protect Banks and Dissipate Energy During High Flows.
Where vegetation is of the stabilizing wetland species, more is better. Winward (2000) notes, depending
on stream type, at least 80% to 98% of stream banks should be covered with stabilizing vegetation or
anchored rocks/logs in order for them to function properly. The water quality benefits realized by
attributes 6-10, Table 1, are only magnified as more of these species/communities grow or expand.
Growing enough to protect banks and dissipate energy will keep banks from eroding, thus keeping
sediment out of the water. Even more will increase nutrient uptake, maintain channel form and habitat
quality, promote more shade and oxygen, and better filter sediment coming from overland flows.
Riparian buffers prevent nonpoint source pollution from entering low order steams and enhance instream
processing of pollutants. Tabacchi et al. (2000) provide a review on the control of runoff by riparian
vegetation, illustrating the physical effects of vegetation on water (Figure 1). Sweeny et al. (2004) found
riparian deforestation caused stream narrowing (presumably due to incision) leading to losses in stream
habitat and compromising in-stream pollutant processing. Streams may also narrow as they pass from
forest to meadow due to dense meadow vegetation Zimmerman et al. (1967) and Davies-Colley (1997).
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Figure 1. Some Physical Effects of Riparian Vegetation on Water Movement and Cycling
1. Slowing and modifying over-bank flow with roughness and turbulence from stems, branches, and leaves;
2. Increasing overbank flow or floodplain access, which increase the wetted surface area and residence time for
infiltration and aquifer recharge.
3. Changing infiltration rate by organic structures and chemistry;
4. Increasing the capillary fringe and soil water storage capacity with fine roots and soil organic matter;
5. Enhancing vegetation growth into the channel to slow water at the margins of wide channels, thus inducing
bank formation;
6. Stabilizing banks to enable meanders to persist and sinuosity to become high, which decreases gradient and
velocity;
7. Narrowing channels so they become and stay coarser (less embeddedness) to enable hyporheic interchange;
8. Decreasing temperature extremes and summer evaporation by narrowing the channel, which decreases
insolation and radiation, and increases hyporheic interchange with more constant temperature groundwater,
and by increasing aquifer discharge and providing shade;
9. Increasing floodplain substrate macroporosity by roots and partitioning by particle size in deposition and
transport;
10. Transpiration;
11. Condensation of atmospheric water and interception of rain, snow, and dew by leaves, etc.
12. Evaporation of intercepted water;
13. Increasing stem flow (the concentration of rainfall by leaves, branches and stems);
14. Permitting flow diversion and sediment storage by logjams; and
15. Increasing turbulence in channel from root exposure and complex channel form.
7 - Plant Communities in the Riparian Area are an Adequate Source of Coarse and/or Large Woody
Debris.
Many rangeland settings in Nevada do not have communities of cottonwood or aspen (Populus spp.) and
are dominated by willows (Salix spp.) or herbaceous vegetation. In these riparian areas, coarse and/or
large woody debris are not needed as hydrologic controls, yet sticks and smaller wood provides function
where it can span channel width. Riparian areas that rely on downed wood need it to slow channel and
floodplain flows and dissipate energy. This allows particulate matter to fall out and further build the
floodplain or reduce channel incision and sediment transport. These communities often have good
overstory cover that provides shade and an evapotranspiration effect, keeping air and water temperatures
cooler. Diverse channel morphology and aquatic habitat (e.g., cover) is created by the large debris, and
water can be oxygenated by plunging over debris. Plant communities that do not provide enough woody
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material weaken riparian functions and make channels susceptible to erosive forces and incision. This
can lead to increases in sediment transport (see item 13) and associated soil nutrient release, changes in
channel geometry, and the associated loss of water quality parameters discussed in attribute 3, Table 1.
For systems where wood or riparian woodlands have an impact on water thermal regimes, their presence
reduces diel variation and temperature extremes (Malcolm et al. 2004). As wood decays, nutrients are
slowly released back into the riparian system to be used by other plants for growth. If decay outpaces
growth, however, an increase of nutrients in the water might be expected. In the 1970s, forest practice
rules allowed harvesting trees relatively close to streams but forbade slash in streams to avoid excess
biological oxygen demand. Later, the rules changed as the importance of wood became understood.
C) Erosion/Deposition Attributes
1 Floodplain and Channel Characteristics (i.e., Rocks, Overflow Channels, Coarse and/or Large
Woody Debris) Adequate to Dissipate Energy.
To some extent these features have already been addressed (i.e., floodplain in attribute 1, coarse and/or
large woody debris in attribute 12, Table 1). The key question for physical functionality is related to their
adequacy, enough of the right features to create friction and dissipate energy for the geomorphic setting.
Attribute 1, Table 1 relates to floodplain accessibility. This attribute relates to its size and energy
dissipating characteristics, especially important as the abandoned floodplain's role is replaced by an
emerging floodable area after incision. The implication to water quality is related to slowing the erosive
powers that create and transport sediment and nutrients/pollutants or not. This slowing not only decreases
sediment transport by encouraging deposition, it also increases water residence time so plants can process
nutrients/pollutants. With more surface area over a wide floodplain and overflow channels and friction
with roughness elements (e.g., rocks, debris), water velocity decreases. Interaction with the air across a
wide or turbulent surface increases oxygen in the water. Adequate vegetation on the banks is discussed
under attribute 11, Table 1, but also important is adequate vegetation on the floodplain to add to the
roughness elements. There must be enough roughness to handle high flow events without degrading the
channel, changing channel geometry characteristics addressed in attribute 3, Table 1. Vegetation favors
the deposition of sediment by increasing roughness and reducing flow velocity. Sedimentation rates
increase where riparian vegetation is present (Girel and Pautou 1997).
2 Point Bars are Revegetating with Riparian-Wetland Vegetation.
This attribute is addressed by a combination of attributes 4, 7 and 9, Table 1. Point bars are formed
through deposition of coarse sediment. With growing vegetation on this coarse material, the stability and
roughness decreases flow velocities, allowing deposition of finer suspended sediment. The fine
particulate suspended sediments and organic matter is the size fraction most likely to contain higher
concentrations of nutrients and hold or elevate capillary water which the plants use to grow. Alluvial
soils are nutrient rich due to high clay and organic matter content that retains phosphorus and nitrogen.
Streams with point bars meander through bank erosion where shear stress is higher on the outside of
curves. Vegetation stabilizing deposited sediments and forming banks is important to maintaining
channel width/depth relationships and meander form and sinuosity. Without this stabilizing vegetation,
water quality implications related to attribute 3, Table 1, can arise as channel geometry tries to establish a
new equilibrium during high flow events.
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3 - Lateral Stream Movement is Associated with Natural Sinuosity.
Lateral stream movement, or bank erosion rate, is a natural process for meandering streams. However,
continued functionality demands the movement must be due to the natural processes involved with the
establishment of dynamic equilibrium and not accelerated. Because the appropriate rate relates to the
landscape setting, and therefore to stream geometry, this attribute is strongly tied to attribute 3, Table 1
and its water quality implications. It is also related to bank erosion processes addressed by attributes 9,
11, and 14, Table 1. Accelerated bank erosion can lead to: removal or weakening of colonizing
vegetation, rapid point bar growth, channel widening, channel aggradation, and development of multi-
thread channels and/or mid-channel bars, sediment-filled pools, and silted stream bottoms. Accelerated
channel migration or evulsion can also lead to cut-off meanders and over steepen a stream, causing
accelerated bed shear stress, erosion, and incision with, multiple implications for accelerated lateral
movement (see attribute 3, Table 1). Water quality implications associated with these outcomes include
direct effects of erosion adding sediment and nutrients to the stream. Indirect effects from altered channel
pattern, profile and dimension include changes to water temperatures due to increased insolation in wider
channels, less shading from bank plants, and limited ground water exchange due to fining of streambed
substrate. Vascular plants process nutrients less while more algae grow, and then respire and eventually
die, increasing biological oxygen demand.
4 - System is Vertically Stable.
A vertically stable system is not down-cutting beyond natural rates (generally detectable on the order of
centuries or more), therefore exhibiting normal rates of erosion, which deliver appropriate amounts of
sediment. If erosion accelerates beyond natural rates, the process can lead to headcuts, which quickly cut
headward (on the order of feet per year), incising up through the wetland. The lowered water table
reduces base flows and dries out riparian vegetation (attributes 6-12, Table 1). The stream bottom erodes
away and exposes eroding banks that often represent centuries of accumulated sediment and associated
nutrients, which are then delivered downstream, especially in high flow events. Water quality
degradation often persists for decades or longer until channel equilibrium geometry and riparian functions
are re-established. The incision leads to an inaccessible floodplain (see attributes 1 and 15, Table 1), thus
limiting plants' ability to process nutrients and the floodplain's ability to dissipate flood energy and
recharge the aquifer.
5 - Stream is in Balance with the Water and Sediment being Supplied by the Watershed (i. e., No
Excessive Erosion or Deposition).
When the stream is in balance with the water and sediment of the watershed, the stream will either be at
or getting closer to its equilibrium geometry and the upland watershed will not be contributing to riparian-
wetland degradation (attribute 5, Table 1). If it is not in balance, this attribute is highly related to
attributes 3, 13, 15 and 16, Table 1 and the water quality implications associated with them. An
imbalance causes aggradation or degradation (Lane 1955), causing channels to change form.
Functional Rating
The assessed attributes lead an interdisciplinary team (ID) team to an overall determination of whether the
reach is nonfunctional, functional-at-risk (with an associated trend), or properly functioning. A properly
functioning reach will be resilient to high flow events and will be the most effective at sequestering
and/or mitigating pollutants that enter the riparian system while minimizing the stream's own contribution
to those pollutants. A properly functioning condition yields good water quality, water availability, and
aquatic habitat in relation to its potential (Prichard et al. 1998). A nonfunctional reach will be just the
opposite, not only less effective at storing upland pollution contributions but also contributing pollutants
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that were previously sequestered for long periods. Just how effective at pollution mitigation/contribution
a functional-at-risk reach will be depends upon which attributes are deficient. Ideally, the combined
reaches in a riparian system ought to all function properly for maintaining habitats and water quality.
Ultimately the pollution processing effectiveness for the entire system depends on the interacting
functionality and dynamics of individual reaches. Such interactions are highly complex and worthy of
future study.
Implications to Water Quality: Sediment, Nutrients, Temperature, and Dissolved
Oxygen (DO).
All attributes of the PFC assessment are expected to affect sediment levels (i.e., inputs, storage, and
environment) and therefore affect nutrients. Many affect temperature and dissolved oxygen (DO). Table
1 summarizes expected benefits ("Yes" responses) or detriments ("No" responses) for each of the PFC
attributes. Note that the checklist items in hydrology, vegetation, and erosion/deposition groups are
intended to aid an interdisciplinary team in observing indicators of opportunities for improved
management to restore or maintain PFC. PFC is the condition sustaining the many water quality benefits.
Yet the individual items also suggest direct and indirect relationships to water quality. An increase in a
relevant PFC attribute generally contributes to a decrease in sediment movement, an increase in nutrient
sequestration, a moderation of temperature extremes, and stabilization in DO. A decrease in functionality
contributes to declining water quality.
Table 1. Summary of Water Quality Implications of Checklist Item Responses in PFC Assessment.
Water Quality and Aquatic Habitat Responses to PFC Attribute Condition
PFC Attribute
Yes
No
Floodplain above
bankfull is inundated
in "relatively
frequent" events.
Capture and store water, nutrients, and
sediment; dissipate flood energy and
decrease erosion, TP and TN; diminish
magnitude of downstream floods by
increasing detention time and facilitating
riparian vegetation.
Increased sediment, TN, TP, and
turbidity. Less discharge in base flow and
shorter high flow periods, putting more
stress on banks.
Where beaver dams
are present are they
active and stable?
Better aquifer recharge and pond storage to
sustain riparian vegetation and base-flow
conditions; increased sediment deposition
and valley bottom widening; increase in fish
refuge - cooler water on pond bottoms and
in water returning to the stream from the
aquifer; nutrient sequestration and
denitriflcation; increase in fecal coliforms;
decrease in trace metals - reducing
environment in the upper 2 cm of the
sediment.
If beaver dam blows out, short-term burst
of water and long-term increase in
sediment, nutrients, microbiota, and other
stored materials delivered to the stream
due to increased risk of channel incision;
loss of pond habitats.
Sinuosity, width/depth
ratio, and gradient are
in balance with the
landscape setting (i.e.,
landform, geology, and
bioclimatic region).
No accelerated erosion or release of
chemicals sequestered in riparian
sediments; stable water temperature and
flow of water and sediments.
Accelerated erosion of soil and chemicals
stored in riparian alluvium; altered
aquatic habitat; floodplain access often
diminished and flow variation increased if
channel steepened; increased temperature
fluctuations if channels are widened;
aquatic habitats degraded.
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Riparian-wetland area
is widening or has
achieved potential
extent.
More area of vegetation uptake of nutrients;
increased sediment and trace metals
capture; decrease in temperature with
increased shade or narrower channel and
hyporheic exchange.
Missed opportunities and often a
downward trend toward increased risk of
Upland watershed is
not contributing to
riparian-wetland
degradation.
No unnatural rate of sediment or water
supply sufficient to destabilize the riparian
system by exceeding its resilience; riparian
functions continue.
Accelerated erosion and supply of fine
sediment contributes pollution. Increased
or decreased bedload or peak flows alter
channel pattern, profile, and dimension.
This can release stored riparian sediment,
nutrients, and other materials, especially
if alteration causes incision.
Evapotranspiration from excess woody
vegetation may diminish base flow and
habitats and stress riparian vegetation.
Diverse age-class
distribution of
riparian-wetland
vegetation
(recruitment for
maintenance/recovery).
Recruitment and survival of various age
classes ensures that plants continue their
roles in riparian functions (e.g., nutrient or
pollutant uptake, slowing flows, and
stabilizing banks to restore or maintain
form) without future excess risk.
Missing age classes are missed
opportunities and are often diminished
functions (uptake, roughness, and soil
binding). Missing recruitment leads to
future risk.
Diverse composition of
riparian-wetland
vegetation (for
maintenance/recovery).
[species present]
Diversity of plants taking up diversity of
nutrients at various times, trapping
sediment of various sizes in slowed water on
various geomorphic surfaces; stabilizing
banks with roots throughout the soil profile.
All with continuity and backup.
Risk of monoculture type failure and
increased likelihood that important
functions (uptake, roughness, and soil
binding) will not be performed by missing
species.
Species present
indicate maintenance
of riparian-wetland
soil moisture
characteristics.
Riparian root abundance and depth much
greater in moist or saturated soil; this
stabilizes streambanks and fuels
denitrification in the zone between aerobic
and anaerobic conditions.
Drier plants lead to weakened roots and
increased bank erosion, risking
conversion to much less stable channel
forms.
Streambank vegetation
is comprised of those
plants or plant
communities that have
root masses capable of
withstanding high
streamflow events.
[community types
present]
Dense root systems stabilize undercut
banks, creating fish refuge and decreases in
temperature from shading. Roots and stable
banks dampen volatility by maintaining
roughness, channel form, and pattern. This
diminishes pollution from erosion.
Vegetation well anchored against high flows
persists to continue functions (e.g., uptake
and shade).
Weak roots allow accelerated bank
erosion and alteration of channel pattern,
profile, and dimension. This unleashes
stored materials that cause sedimentation
and eutrophication, while increasing
insolation, radiation and water
temperature extremes and degrading
habitat.
10 Riparian-wetland
plants exhibit high
vigor.
More uptake of nutrients slows the nutrient
spiral and decreases eutrophication. More
vigor leads to more reproduction for
maintenance and recovery-
Weak plants fail to function optimally,
leaving bare areas, faster export of
riparian materials, and greater risk of
collapse.
11 Adequate riparian-
wetland vegetation
cover present to
protect banks and
dissipate energy during
high flows [enough?]
Adequate vegetation performs vegetation
roles discussed above sufficiently well to
maintain functions through large flow
events (20-25 year flows).
Inadequate stabilizing vegetation poorly
performs riparian functions and risks
major channel alterations in high flows
18
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12 Plant communities are
an adequate source of
coarse and/or large
woody material (for
maintenance/recovery).
Wood stabilizes to form plunge pools that
dissipate energy. It provides habitat and
stores water, sediment, and
nutrients/pollutants. The woody plant
communities provide shade-ameliorating
water temperature and roots to reinforce
channel form.
Loss of wood and woody plant community
increases risk of losing structural
reinforcement needed to maintain channel
form and retain stored materials.
13 Floodplain and
channel characteristics
(i.e., rocks, overflow
channels, coarse
and/or large woody
material) adequate to
dissipate energy.
Dissipation of flood energy allows riparian
functions to protect and restore habitats and
water quality against the destabilizing
effects of exponentially increased stream
power.
Undissipated stream power can
fundamentally alter channel and riparian
form and function causing sequestered
sediment, nutrients, and organic and
other materials to be rapidly exported.
Loss of form and function then continues
this export with habitat degradation.
14 Point bars are
revegetating with
riparian-wetland
vegetation.
While point bars are natural locations for
bedload deposition, riparian vegetation
helps build the veneer of fine sediment that
converts a point bar into a floodplain with
stable banks. Thus, pointbar riparian
vegetation decreases sediment and nutrient
transport by inducing deposition, rebuilds
or maintains a stable meander pattern with
a low width/depth ratio channel between
stable banks, and this aids denitrification
and uptake and as hyporheic water flows
under riparian vegetation on point bars.
Absence of riparian vegetation misses
opportunities for slowing flows, inducing
sediment and organic matter deposition,
nutrient uptake, and riparian habitat
restoration.
15 Lateral stream
movement is associated
with natural sinuosity.
Erosion at a natural rate allows
maintenance of channel pattern, profile and
dimension, and floodplain access with its
functions of flood energy dissipation;
floodwater capture to support riparian
vegetation and base flows; and regulation of
sediment and nutrient fluxes.
Accelerated lateral movement through
excess bank erosion of channel evulsion
risks channel incision with greatly
accelerated input of sediment and
nutrients, often indicated by unstable
mid-channel bars and only short-term
sequestration.
16 System is vertically
stable. (i.e., not
downcutting)
Stability decreases risk of rapid input of
stored materials and facilitates riparian
functions, uptake, energy dissipation, and
soil binding.
A system that has a headcut or an over-
steepened reach is likely to erode
headward, causing channel incision.
Erosion and export of stored riparian
materials then pollutes water and
degrades habitats and diminishes function
for many years, even decades.
17 Stream is in balance
with the water and
sediment being
supplied by the
watershed (i.e., no
excessive erosion or
deposition).
With the stream having the pattern, profile
and dimension needed to transport the
water and sediment being supplied by the
watershed, riparian functions can continue
to dissipate energies, stabilize banks, and
maintain or improve water quality and
habitats. Gradual changes allow systems to
adjust form to match function.
Excessive sediment supply, a channel too
wide, or insufficient water to transport
sediment load can lead to aggradation
which damages aquatic habitat by filling
pools, and it can lead to grossly altered
form. Insufficient sediment (e.g., hungry
water below a reservoir), or too much
water can incise a channel and accelerate
erosion of fine, nutrient-rich bank
materials. Rapid or excessive changes
overwhelm internal adjustment processes.
19
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Justification
The current system of water quality regulation focuses on the total maximum daily load (TMDL) process.
Water quality monitoring is often implemented to ascertain pollutant levels. Across the U.S., hundreds of
millions of dollars are spent each year by private enterprise, education and research facilities, government
agencies, and others to monitor water quality in streams and rivers; although an accurate estimate has not
been found, the USGS (2012) alone has budgeted some 62 million dollars to its National Water Quality
Assessment program for 2013, and the USEPA (2012) has budgeted 3.8 billion dollars toward its
Protecting America's Water goal. Acceptable levels of pollutants are set by comparing the beneficial uses
for which each water is used to standards established for each use. Waters not meeting standards for their
designated beneficial uses go on the states' list of impaired water bodies (the 303(d) (section of the Clean
Water Act) list). This initiates the TMDL process. A TMDL is set for each listing, usually based on
modeling predictions that consider, among other things, sources, flows, estimates of pollutant
concentrations, and waterbody assimilative capacity. The TMDL is then allocated among the landowners
and potential sources of pollution in the watershed. Education/funding toward best management practices
to keep pollutants from entering the waterway are usually the first efforts made to protect the system.
Unfortunately, allocation of loads does not necessarily reflect opportunity to reduce pollution. Many
streams (and other types of water bodies) are themselves the source of sediment, or nutrients, due to their
failure to function properly. These often have extreme temperatures and sediment/nutrient loads, low
DO, and poor habitat for aquatic organisms. In these cases, reducing an external load is not the solution.
Rather, riparian functions must be restored to reduce pollution-releasing processes like erosion and
engage assimilation processes that slow the nutrient spiral with flooding, uptake, and complex niches and
food webs. This system of water quality regulation is fraught with complications that can make the
TMDL system all but ineffectual at reducing pollution levels. One problem is the assumption that the
landowners, users, and managers have control of the pollutants and are the sole sources. The source of
pollution addressed by this study is the stream and riparian area due to its nonfunctional or functional at
risk physical condition. In 2000, the BLM reported that in Nevada only 30% of riparian miles and 26%
of wetland acres were functioning properly (BLM 2001). This clearly limits the ability of the TMDL
process to make any progress toward meaningful water quality improvement in these areas, because the
waterway is the pollution source. Water quality and aquatic habitat, particularly in rural areas, can be
improved by returning riparian/wetland systems to a functional condition. Once in a functional condition,
riparian areas can act as pollutant processors helping to mitigate water quality before it enters the
waterway. Only by including the functionality of the riparian system can the TMDL process effectively
address water quality issues. Furthermore, water quality also embraces the physical and biological, not
just the chemical, aspects of habitat, and properly functioning riparian areas provide far more complex
and biologically productive aquatic habitat.
Objective and Hypotheses
The primary objective of this study is to document changes in riparian land management to effect
physically functional riparian condition of streams and test hypotheses related to changes in water quality.
Maggie Creek in north-central Nevada serves as a case study location. It was chosen for its relatively rich
water quality data sets and dramatic change in riparian land management leading to significant
improvements in riparian zone physical functionality in small parts of the watershed having most of the
important perennial stream habitat,
20
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Conditions Affecting Hypotheses Development:
Water quality datasets, spanning the entire time of this study, are only available at:
o MAG2 (site established in middle section of Maggie Creek by Newmont Mining Corporation,
hereafter referred to as the "upper station").
o Simon Creek (site established on Simon Creek near confluence with Maggie Creek by
Newmont).
o MAGI & HS14 (sites established on Maggie Creek closer to the Humboldt River confluence
by Newmont (MAGI) and the Nevada Department of Environmental Protection (HS14),
hereafter referred to as the "lower station").
Water quality parameters collected differ slightly among the stations.
Results of PFC assessments given in full detail.
Hypotheses
1. Because of the improved functional attributes and condition above the upper station, all water
quality parameters addressed by this study will generally trend toward improvement through
time, that is:
Improved base flows (higher flows, increased duration)
Decreased TSS
Decreased nutrients (TN, TKN, and/or NOx; OP)
Increased summer DO
Decreased summer water temperature
2. For the same reason, aquatic habitat features will also show improvement through time:
Increased riparian condition class
Decreased width to depth ratio
Increased riparian zone width
Increased shorewater depth
Increased woody riparian vegetation overhang (shading)
Increased pool quality
3. Because of the minimal improvement of functional attributes and condition of stream reaches
between the upper and lower station, the lower station will demonstrate the residual effects of
water quality improvement of trend from above, but to a lesser degree.
21
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Site Description
The Maggie Creek Watershed is in northeastern Nevada within the northern Great Basin (a temperate
desert with cold snowy winters and hot dry summers) and drains to the Humboldt River basin (Figure 2).
Maggie Creek Watershed is bounded by the Tuscarora Mountains on the west and the Independence
Mountains to the north and east. The National Hydrologic Dataset (NHD) indicates the Maggie Creek
Watershed has 1,094 stream miles, predominantly intermittent or ephemeral, with 224 miles of perennial
reaches (Figure 3). Elevation ranges from about 1435 to 2700m. The Maggie Creek Watershed covers
254,150 acres, of which BLM administers 42% and manages eight smaller and three large grazing
allotments (Figure 4), 55% is privately owned and 3% is owned by the state of Nevada (Figure 5).
Figure 2. Study Area, Maggie Creek, NV.
Most of the watershed is in the Upper Humboldt Plains level 4 ecoregion (Bryce et al. 2003) except for
the Semiarid Uplands of the Tuscarora Mountains on the basin's west side (Figure 6). The Tuscarora
Mountains supply most of the runoff for Maggie Creek. Most precipitation is deposited as snow,
especially at higher elevations. Snowmelt and spring flow is the major source of water feeding the
streams in this study. The thirty year average (1970-2000) precipitation of the watersheds in the general
area range from 284-830 mm (11.2-32.7 inches). Land cover is primarily shrub/scrub of short and
mountain big sagebrush (Artemisia tridentata Nutt. ssp. Vaseyana) with Idaho fescue (Festuca idahoensis
Elmer) and other grasses. Some juniper and aspen forests occupy headwater areas of tributaries.
Riparian vegetation consists primarily of willow communities. There are smaller meadow areas of
hay/pasture production located mostly along waterways (Figure 7). The primary land uses include
ranching, hay production requiring diversions of stream water, and mining. As described, Maggie Creek
is a microcosm representative of the northern Great Basin.
During the period of this study, the 2001 Coyote Fire burned 11,637 acres primarily in the Beaver Creek
sub-basin. In the same year, the Maggie Creek Fire burned approximately a 2,550 acre portion on the east
side of the lower portion of the watershed. The Basco Fire, in 2006, burned approximately 11,750 acres
22
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within the watershed on the east side in the upper portion of the watershed (Figure 8). Collectively, 9.8%
of the watershed burned during this study.
N
Beaver Creek
Coyote Creek
Jack Creek
Simon Creek
James Creek
Mountain
Creek
Chicken Creek
Coon Creek
Cottonwood Creek
Cherry Spring
Figure 3. Maggie Creek, NV, River Reach and 12-Digit Hydrologic Units.
23
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N
ti
Hydrologic Boundary
BLM Allotments
H BLUE BASIN
| | EAGLE ROCK
FOX SPRINGS
HADLEY
LONE MOUNTAIN
J MARY'S MOUNTAIN
| | MCKINLEY FFR
HH PRIVATE
| T LAZY S
HI TAYLOR CANYON
||TUSCARORA
TWENTY FIVE
Figure 4. Maggie Creek, NV, BLM Grazing Allotments and largest ranches.
24
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Hydrologic Boundary
Hydrologic Units
River Reach
Land Ownership
| | BLM
^m PVT
Figure 5. Maggie Creek, NV, Land Ownership.
25
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N
Upper Humboldt Plains
Figure 6. Maggie Creek, NV, Ecoregions.
26
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River Reach
~ Hydrologic Boundary
Hydrologic Units
Land Cover
Open Water
Urban
Barren Rock/Sand/Clay
Deciduous Forest
Evergreen Forest
Mixed Forest
Shrub/Scrub
Grassland/Herbaceous
Pasture/Hay
Cultivated Crops
Woody Wetlands
Emergent Herbaceous Wetlands
Figure 7. Maggie Creek, NV, National Land Cover Database Homer et al. (2007).
27
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N
| | Hydrologic Boundary
'"" 2001 fires
12006 fires
V
Coyote
Figure 8. Maggie Creek, NV, Fire Event Areas.
28
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History
Commercial ranching probably started in the watershed in the late 1870's around the time the T Lazy S
Ranch was amassing vast acreages via homesteading and railroad land acquisitions. Land use then
consisted of open range grazing and developing irrigated hay production, particularly in the Rock Creek
and Humboldt drainages. The T Lazy S Ranch has since been renamed the TS Ranch, which today has
private holdings and grazing allotments within the Maggie Creek Watershed. The Maggie Creek and
Twenty-Five ranches also operate within the watershed. The TS Ranch is managed by the Elko Land &
Livestock Company, a subsidiary of current owner Newmont Mining Corporation (Newmont), which
purchased the ranch in 1986 to gain mineral rights, water rights, and transportation access.
The Carlin Trend, a 50-mile long, 5-mile wide belt of faulted terrain runs northwest to southeast from the
town of Carlin, Nevada, through the Maggie Creek Watershed. The Carlin Trend has been called the
most prolific goldfield in the Western Hemisphere. Newmont started open pit production on the Carlin
Mine (within the lower portion of Maggie Creek Watershed) in 1965. With the discovery of higher grade
gold at depth, underground mining began in 1994, necessitating mine water extraction and mitigation
(BLM 1993).
Prior to 1993, the majority of Maggie Creek was grazed by cattle throughout the growing season,
resulting in impacts to riparian vegetation and degraded stream conditions. Decades of intensive grazing,
water development, and road construction degraded aquatic and riparian habitats. By the early 1990's,
miles of stream were characterized by unstable banks, channel incision, riparian vegetation loss, wide
shallow channels, excessive erosion and deposition, reduced stream flows, and increased water
temperatures. This left degraded reaches in physically nonfunctional or functional-at-risk condition
(Prichard et al. 1998) and fragmented critical habitat for the Lahontan Cutthroat Trout (LCT), causing
their populations to decline.
The LCT, Nevada's state fish, was listed as threatened under the Endangered Species Act in 1975 and
remains so today. The Maggie Creek drainage was historically renowned for its fishery and now supports
multiple remnant LCT populations. Maggie Creek basin is considered one of only a few watersheds in
northeastern Nevada that could support LCT metapopulations (multiple populations within an area in
which interbreeding could occur), but does not due to geographic barriers.
As mitigation for their 1993 South Operations Area Project (SOAP, mine dewatering), Newmont, in
cooperation with the Elko District Bureau of Land Management (BLM) and the Elko Land and Livestock
Company, developed the Maggie Creek Watershed Restoration Project (MCWRP) to improve streams,
riparian habitats, and watershed conditions within the Maggie Creek Basin (BLM 1993). The project was
developed to enhance 82 miles of stream, 2,000 acres of riparian habitat and 40,000 acres of upland
watershed primarily through prescriptive livestock management.
Beginning in 1994, grazing systems were implemented for portions of the perennial/intermittent streams
and the twenty-five ranch allotments in the Maggie Creek Watershed (specifics found in Evans 2009).
This greatly reduced the frequency and duration of hot season grazing on Maggie Creek and its
tributaries. The area is divided into three zones including exclusion zones, a restoration zone, and a
controlled grazing zone (Figure 9). The exclusion zone is closed to grazing while livestock use of the
restoration zone is contingent on meeting and maintaining biological standards. The controlled grazing
zone provides for rotational and deferred grazing practices. The extent of restoration accomplished by
focused riparian grazing management is illustrated by the front cover of this publication. Both the
exclusion and restoration zones support LCT habitat. Other measures, including construction of water
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developments, tree plantings, prescribed burning, and development of a conservation easement were also
part of the restoration effort.
The primary focus of the plan was to improve LCT habitat. Other efforts to improve fish populations
included replacing culverts and irrigation diversions that bar migration, and placement of barriers at the
bottom of the watershed to keep out non-native fish species. Trout Unlimited and partners are working
within the watershed to monitor fish population response due to habitat improvement and barrier removal.
Land uses that most significantly affect water quality and aquatic habitat issues elsewhere in the
Humboldt basin include grazing, irrigation agriculture, and mining. Changing the land management of
grazing and agricultural uses leads to changes in riparian functionality, which affects water quality and
aquatic habitat variables. Changes in active mining management, in its current form, will likely not lead
to changes in PFC. Exceptions would be accidental release of acid mine discharge (AMD), and
deposition of excess sediment and/or flocculants (e.g., iron precipitates). Changes in PFC are not
expected to significantly change water quality issues associated with mining (i.e., heavy metals, soluble
metals, mineralization, and low pFi). However, increased organic matter will provide binding sites for
suspended and dissolved trace metals. There is also an ancillary effect via the absorption of soluble trace
metals by riparian wetland plants, and deposition due to slowing of stream flows. Mine dewatering can
lead to lowering water tables and reduced or augmented flow in stream channels, which is occurring in
areas of Maggie Creek below where grazing management has changed.
Impacts to PFC are far more prevalent from grazing, agricultural use, and roads than from mining in the
Humboldt Basin, including Maggie Creek. Water quality variables that most closely respond to changes
in land use/management in the Humboldt Basin include sediment (turbidity, total suspended solids), flow
alteration (quantity, timing), nutrients, temperature, dissolved oxygen, pathogens and trace metals.
Important aquatic habitat variables include riffle/pool ratios, bankfull width/depth ratios, embeddedness,
and bank stability.
Water Quality Stations
Four sample collection stations have water quality data spanning the entire period of this study. Other
stations have data from much shorter periods, and are of limited or no use. Stations MAGI (Newmont),
HS14 (Nevada Department of Environmental Protection (NDEP)), and 1032200 (USGS) are within a
quarter mile of each other (the "lower station"). Station HUM82 (EMAP, with a single sample date, July
1998) is about two and a half miles upstream of these stations. All are at the bottom of the watershed near
the confluence to the Humboldt River. The "lower station" therefore represents water quality resulting
from traveling through a physically poor or non-functional series of reaches with numerous water
diversions for hay field irrigation. Station MAG2 (the "upper station") is about 6.5 miles upstream of the
lower stations, just above the mine reservoir flow augmentations, and below the Maggie Canyon narrows
about 4.5 miles below the first pasture with a change in management. Station locations are shown in
Figure 9.
30
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012345 Miles
I I I I I I
*t&
1032200 * MAG1
Management Change
Beginning circa 1994
Water Quality Stations
Streams
MCWRP Area
Managment
Exclusion
Restoration
££3 Controlled
BCRP
Maggie Watershed
Figure 9. Management Change and Water Quality Stations in the Maggie Creek Watershed Restoration Project
(MCWRP) and the Beaver Creek Riparian Pasture (BCRP), NV.
Water Quality Data Available
Sources of water quality data within Maggie basin include Newmont, NDEP, USGS, and the EPA. The
dates of data collection are displayed on the hydrograph in Figure 10, which demonstrates good
representation of data across many flow discharges. Noted also is the increased occurrence of data
collected during periods of no flow starting in 2001, corresponding to a loss of continuous base flows
discussed in Results. The parameters collected at any particular time are highly variable. Water quality
data collected above the influence of mining activity and associated with flows as recorded at station
10321950 come exclusively from Newmont's data collection at station MAG2, which is approximately
two and a half miles downstream of the USGS station and just upstream of where reservoir water is
discharged to Maggie. Both NDEP's station HS14 and Newmont's MAGI station are within a quarter
mile upstream of the USGS station 10322000. The EPA's station HUM82 is about 2.8 miles upstream of
the USGS gage.
-------
USGS Station 10321950, Maggie Cr. @ Maggie Cr. Cyn near Carlin, NV
100
f
a
WQData Available
J-90 J-91 J-92 J-93 J-94 J-95 J-96 J-97 J-98 J-99 J-00 J-01 1-02 1-03 1-04 1-05 1-06
Figure 10. Water Quality Data Available at USGS Gage Station 10321950 on Hydrograph, Maggie Creek, NV..
Methods
Assessing Stream Functional Condition
Stream functional condition was assessed using the methods of Clemmer (1994) and Prichard et al.
(1998). Evaluations were performed by an interdisciplinary team composed of a hydrologist,
geomorphologist, and ecologist for the years 1994 and 2006 because of the availability of imagery. The
year 1994 is important because it preceded management changes, and 2006 reflects recent conditions
within the period of water quality data. Much of this was done through remote sensing data in ArcGIS.
2006 Color Infrared (CIR) and National Agriculture Imagery Program (NAIP) 1-meter resolution imagery
was used (with other ancillary data) to assess PFC condition for 2006. 1994 black-and-white (B&W)
Digital Orthophoto Quarter-Quadrangles (DOQQs) and CIR 1-meter imagery (with other ancillary data)
were used to assess PFC for 1994. 1994 CIR imagery (obtained from the BLM) is not complete for the
entire Maggie Creek Watershed. It covers the major tributaries of Simon Creek, Jack Creek, Coyote
Creek, and Spring Creek as well as Maggie Creek proper upstream nearly to Beaver Creek. Beaver Creek
and the main channel and tributaries to the north were evaluated with B&W only. While some
interpretations about vegetation status can be made using B&W photography, use of these images limits
what interpretations can be made in the vegetation category of PFC assessments. For both years, some
on-the-ground photography was available from stream surveys performed by the BLM. Very Large Scale
Aerial (VLSA) imagery was flown by Open Range Consulting in 2006 (provided by the BLM) for some
32
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portions of Maggie Creek, Coyote Creek, and Beaver Creek. Where available, all these images were used
to help assess PFC condition.
Ancillary data used for PFC assessments include: the USGS NHD showing springs, water bodies, and
perennial and intermittent streams; landowner polygons from the BLM; landcover rasters from the USGS
National Land Cover Database 2001; USGS topographic maps; pasture polygons from the BLM; and
stream survey locations from the BLM. Several other layers have helped to a lesser degree.
Assessing PFC over hundreds of miles is a large task even when using aerial photography. However,
investigations indicate many of the perennial stretches of stream in the upper watershed fail to connect to
Maggie Creek in any but the more significantly large hydrologic events. In most cases, the larger
tributaries of Jack's, Coyote, and Beaver creeks go sub-surface as they flow into the alluvial deposits at
the base of the Tuscarora Mountains, except perhaps briefly in the early spring during the snowmelt
runoff of a good snow year. In most years, surface water contributions from tributaries to water quality in
Maggie Creek are negligible. Therefore, it is not relevant to downstream water quality to evaluate the
PFC of the upper reaches. Similarly, downstream water quality measurements cannot be used to
understand water quality or habitats in these headwater reaches. However, in the lower portion of the
larger tributaries, springs return sub-surface flow to lentic and lotic systems that remain perennial or at
least intermittent. These springs and seeps, as well as occasional surface waters and riparian conditions,
likely influence water quality of Maggie Creek.
"Reach rules" were developed to help determine which segments (reaches) of streams were likely to
significantly influence water quality and therefore, which reaches we would complete a PFC assessment
for in both years.
Use reach rules:
1. There must be perennial flow on the stream (Maggie Creek proper) or primary, secondary, or
tertiary tributary (unless tertiary is insignificant).
2. Tributaries must have at least an intermittent connection to Maggie Creek.
3. Ephemeral reaches above uppermost perennial sections don't count.
4. Secondary and tertiary tributaries less than 0.5 miles are not considered.
5. Delineated reaches will be homogeneous in their potential, based on geomorphology and plant
community complex (Winward and Padgett 1987 and Burton et al. 2011) and apparently in their
management, and generally no shorter than 0.25 miles.
6. Where there is no indication of riparian vegetation, a reach will be assumed to be ephemeral, and
thus any perennial or intermittent reaches above this will be ignored.
To ground truth and validate observation made via remote sensing images, a field visit to Maggie Creek
was made on April 9 & 10, 2010. A laptop with the geographic information system (GIS) project
coupled with an interactive global positioning system (GPS) was used to help verify location in the field
and find points of interest with relative ease.
Precipitation and Discharge
Data for precipitation was obtained from the National Oceanic and Atmospheric Administration (NOAA)
National Climatic Data Center (http://www.ncdc.noaa.gov/oa/ncdc.html) for the Elko airport, the closest
available data source that spans the time of the study. Stream flow data were obtained from the USGS
33
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National Water Information System (NWIS, http://waterdata.usgs.gov/nwis) for the stations 1031950 and
1032200 within the Maggie Creek Basin. Station 1032200 does not have data for 1990-1992. The 1993
data from the two stations was used to create a predictive regression model to fill in relatively dry 1990-
1992 data gaps.
Water Quality and Aquatic Habitat Data
Water quality data for the stations HUM82, HS14, 1032200, and MAGI (Figure 9) were combined to
represent the "lower station" as the one lowest in the watershed location and associated with flow data
from station 1032200. MAG2 (upper station) water quality data were associated with flow data from
station 1031950, representing a location further up in the watershed. There were no flow data available to
associate with the Simon Station, which represents a tributary location of static or slightly degrading
physical functionality.
In order to prevent bias of predictions, this study did not analyze water quality data until PFC-based
hypotheses were developed. However, the general natures of data sets were examined to select variables
for testable hypotheses.
Analyses included trend of each water quality parameter. Students T-tests compared early to late study
period data means and F-tests compared variances. In some instances medians were tested as data were
skewed. The length of early or late period data depended on data availability, but generally focused on
data from 1990-1993 (pre-management change period) compared to 2003-2006. Four years of data
including at least one high flow event represent each period.
Total Suspended Solids (TSS)
TSS is known to be related to discharge. Therefore, in addition to the above mentioned general analyses
of the parameters, sediment rating curves were developed to examine trends between sites. Having
sufficient data necessitated using longer early (1990 to 1996, upper station; 1993 to 1999, lower station)
and late (2000 to 2006, upper station; 2002 to 2008, lower station) periods.
Orthophosphate Phosphorous (OP-P)
Of four different types of phosphorus parameters collected, none span the entire range of dates for either
the upper or lower station. OP-P has more coverage than most, with considerable overlap with other
phosphorous parameters, especially at the lower station. Where overlaps occur, regression analysis is
used to establish relationship models (R2 = 0.934 to 0.986, depending upon TSS concentrations) between
parameters and used to estimate OP-P values where gaps existed. Phosphate transport is associated with
sediment transport (and therefore discharge), so phosphate rating curves were developed to examine
trends between sites. As with TSS analysis, this necessitated using longer early and late periods.
Nitrogen (Total Nitrogen (TN), Total Kjeldahl Nitrogen (TKN) and Nitrate/Nitrite (Nox))
The upper station has very limited nitrogen data. TN is the sum of TKN (nitrogen bound by organics)
and NOx (inorganic nitrogen sources). The lower station has better data coverage for TKN, but is
missing some TN (14% of those with any data) and almost all NOx. Regression analysis is used to
establish a relationship between TN and (R2 = 0.784) with TKN and the model used to fill in TN data
gaps where they existed. NOx gaps were filled in by subtracting TKN from TN.
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Dissolved Oxygen (DO)
DO concentration (mg/L) data were used in this analysis. Data are more limited at the upper station.
Concentrations between 6 and 9 mg/L are generally desired for maintenance of aquatic health in cold
freshwater fish habitat (EPA 1988).
Water Temperature
Air temperature data obtained from the NOAA National Climatic Data Center, Elko airport, are used to
compare water temperature trends at the two Maggie Creek locations.
Results
Stream Functional Condition
Approximately 53 stream miles were assessed as 98 reaches (Figure 11) as defined by the reach rules
described in Methods. Comparison of Figures 9 and 11 reveals that most of the restoration and controlled
grazing zones and all of the Beaver Creek Riparian Pasture are outside of the accessed reaches. The
perennial upstream reaches valued for fish and riparian habitat were isolated from downstream reaches
and were not expected to influence water quality at sampling stations except during unusually high flow
conditions. Downstream exclosure, restoration, and controlled grazing pastures comprised 14 of the 53
miles assumed to most directly affect water quality.
Figure 11. PFC Stream Reaches Assessed Along Maggie Creek, NV.
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PFC assessments found no instances where upland watershed is contributing to riparian degradation
(attribute 5). As mentioned previously, open pit mining is prevalent in this watershed, but aerial images
revealed no evidence that tailings or sediment from erosion was making its way into any of the studied
stream reaches. Furthermore, no evidence of natural mass wasting or excessive erosive forces that would
contribute to stream degradation was found. One example of mass wasting was high in the Coyote Creek
tributary. It occurred above miles of ephemeral channel and was therefore disregarded as per reach rules.
This indicates that sediment pollution issues are likely to originate from erosional processes within the
stream channel itself.
Determining riparian plant vigor (attribute 10) from the aerial photos was difficult. The influence of
vigor on long-term water quality is also assessed by other PFC variables. Stream stability within assessed
reaches is not dependent upon coarse and/or large woody debris (attribute 12). Where sticks provide a
similar role along small brushy streams, that role is well addressed by items 6 and especially 11 and 13.
Therefore, PFC attributes 10 and 12 are not addressed further.
Table 2 shows the percent change of assessed stream miles for PFC attributes and PFC rating on Maggie
Creek and its tributaries. Note attributes 2, 4, 6, 7, 9, 11, 13, 14, and the functional rating all had more
than 10% change on either Maggie or the total miles assessed. While arbitrary, it was decided 10% or
greater represented a robust enough change for attribute or rating's role to be further evaluated as a driver
of water quality change. While other tributaries had greater percentages of change, the relative length of
stream miles to the whole was small (collectively only
The functional rating of Maggie Creek improved on 13% of the stream miles assessed and constitutes the
largest portion of the 13.2% increase in functionality of the system overall. The largest contributors to
this increase include an increase in active/stable beaver dams, an increase in the diverse age classes,
composition, and amount of adequate we 11-rooted riparian plant communities, and an improvement of
floodplain/channel energy dissipation characteristics.
36
-------
Table 2. Percentage of Stream Miles that Changed According to Attribute, Maggie Creek, NV
Creek
Maggie
Maggie in
the
MCWRP
Simon
Haskell
Coyote
Beaver
Spring
Jack
Total
Miles
Assessed
Stream
Miles
Assessed
33.8
14.2
2.7
3.0
2.7
2.3
2.1
6.0
52.6
% of Total
64%
27%
5%
6%
5%
4%
4%
11%
% Total
Miles
Changed
Hydrologic Attributes
1
3.5%
0.0%
0.0%
0.0%
0.0%
0.0%
35.7%
35.8%
7.8%
2*
28.6%
56.7%
0.0%
20.3%
0.0%
0.0%
0.0%
0.0%
19.5%
3
6.7%
13.5%
13.1%
-8.1%
0.0%
0.0%
0.0%
35.8%
8.6%
4*
8.9%
0.0%
2.6%
-22.3%
52.6%
0.0%
35.7%
52.4%
14.7%
Vegetative Attributes
6*
12.3%
23.7%
-3.0%
-36.8%
31.4%
0.0%
0.0%
0.0%
7.3%
7*
10.5%
19.1%
-3.0%
-26.4%
62.7%
0.0%
35.7%
0.0%
9.8%
8
2.3%
0.0%
-3.0%
-11.5%
31.4%
0.0%
35.7%
35.8%
7.8%
9*
17.4%
28.9%
-0.2%
-21.1%
0.0%
0.0%
35.7%
35.8%
15.5%
11*
20.6%
39.9%
10.0%
-31.9%
0.0%
0.0%
35.7%
71.5%
21.6%
Soils, Erosion/Deposition Attributes
13*
11.8%
19.9%
5.5%
-29.4%
0.0%
0.0%
35.7%
35.8%
11.7%
14*
7.5%
3.7%
-0.2%
-15.0%
31.4%
0.0%
71.4%
46.3%
13.7%
15
-1.0%
0.0%
0.0%
0.0%
0.0%
0.0%
71.4%
-7.3%
1.3%
16
6.7%
8.5%
0.0%
0.0%
0.0%
0.0%
71.4%
-35.8%
3.1%
17
-2.5%
-5.9%
-3.0%
-6.1%
-17.0%
0.0%
0.0%
-35.8%
-7.1%
Functional
Rating*
13.0%
26.8%
2.8%
-15.2%
0.0%
0.0%
35.7%
35.8%
13.2%
Fbsitive values represent overall improvement w hile negative values represent overall degradation. "Values on either Maggie Cr. or the entire assessed system greater than 10% we consider a robust measure of change for further evaluation.
Attribute: 1) Floodplain inundated in relatively frequent events (1-3 years); 2) Active/stable beaver dams; 3) Sinuosity, w idth/depth ratio, and gradient are in balance w ith the landscape setting (i.e., landforrn geology, and bioclimatic region);
4) Riparian zone is w idening or has achieved potential extent; 6) Diverse age-class distribution (recruitment for maintenance/recovery); 7) Diverse compos iton of vegetation (for maintenance/recovery); 8) Species present indicate
maintenance of riparian soil moisture characteristics; 9)Streambank vegetation is comprised of those plants or plant communities that have root masses capable of withstanding high strearrflow events; 11) Adequate vegetative cover
present to protect banks and dissipate energy during high flows; 13) Floodplain and channel characteristics (i.e. rocks, overflow channels, coarse and/or large woody debris) adequate to dissipate energy; 14) Fbint bars are revegetating;
15) Lateral stream movement is associated with natural sinuosity; 16) System is vertically stable; 17) Stream s in balance with the water and sediment being suppl ed by the watershed (i.e., no excessive erosion ordeposition);
Functional Rating) FFC, FARw/trend, or Nonfunctional.
FAR - Functional At Risk
PFC - Proper Functioning Condition
37
-------
Precipitation and Discharge
Figure 12 shows yearly precipitation for the period of study. Six years had below average precipitation
while eight where above average. Four of the six below average years are clustered together in the
middle of the study period from 1999 through 2002. This precipitation pattern is generally reflected in
the hydrograph displayed in Figure 7. It should be noted, while Elko had below average precipitation in
1993 (as well as 1992 not displayed in Figure 12), there was considerable spring runoff recorded at
Maggie Creek (Figure 13).
Yearly Precipitation in Elko, NV 1985 - 2006
16
10
£ 8
mrm n n
ii
ii
ii
Average Yearly Precip
Figure 12. Yearly Precipitation in Elko, NV.
38
-------
USGS Station 10321950, Maggie Cr. @ Maggie Cr. Cyn near Carlin, NV
1200 T 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 r 10
800
J-90 J-91 J-92 J-93 J-94 J-95 J-96 J-97 J-98 J-99 J-00 J-01 1-02 1-03 1-04 1-05 1-06
Figure 13. Monthly Precipitation at Elko, NV vs. Daily Hydrograph of Maggie Creek, NV.
Two USGS stations have discharge data available for the period of study (1994 - 2006) on Maggie Creek
(Figure 14). Station 10322000 is about nine miles downstream of station 10321950 and is near the
confluence to the Humboldt River. Discharge at 1032200 is influenced by additions from a reservoir built
about seven miles upstream near the time of the beginning of this study to hold water from mine
dewatering activities. As seen in Figure 14, flows prior to the middle of 1994 were generally lower than
the above station. After 1994, flows were higher, marking the beginning of the reservoirs influence.
Yearly peak discharges are similar at the two stations. Above average precipitation is recorded at Elko
from 2003 through 2006 (Figure 12). This is evidenced by higher spring discharges (Figure 13) during
the same time period. There does not appear to be a return of continuous base flows at station 10321950
as there was prior to July of 2000.
39
-------
USGS Station 10321950 (nine miles upstream) Compared to Station
10322000 (near Humboldt River confluence)
J-93 J-94 J-95 J-96 J-97 J-98 J-99 J-00 J-01 1-02 1-03 1-04 1-05 1-06
Station 10321950 Station 10322000
0.01
Figure 14. Comparison of Upstream (Bold Line) and Downstream (Light Line) Gage Stations on Maggie Creek, NV.
40
-------
The cumulative frequency distribution of discharge at station 10321950 (Figure 15) shows that 90% of all
flows are below approximately 55 cfs (bankfull discharge) and 70% are below 10 cfs. No flow is
recorded about 27% of the time. The average flow at this station is about 24 cfs, the median is 4.5 cfs,
and the mode is 0 cfs.
Cumulative Frequency Distribution of Discharge @ Maggie Cyn, 1990-
2006
1
t
c
-------
Total Suspended Solids (TSS)
TSS data collected at the four stations ranged from 0 (non-detectable or ND) to 1100 mg/L. The average
value was approximately 51 mg/L, the median was 12 mg/L, and the mode was 10 mg/L.
Prior to management change, the trend in TSS at the upper station (Figure 16) was highly influenced by
the March, 1993 runoff event. After the change in grazing management in 1994, TSS tended to decrease,
though slightly (R2 = 0.005). Figure 16 demonstrates the need for a sediment rating curve to help
interpret high TSS anomalies.
1 ")nn
1 nnn
snn
00
Scnn
l/>
Ann
0 -
J-
TSS through Time @ Upper Station
* 1990-1993
0 1994-2006
Trnnrl Ofl T?
Trend 94-06
0 °
/ o
90 J-92 J-94 J-96 J-98 J-00 J-02 J-04 J-06
Figure 16. TSS Trend at Upper Station, Maggie Creek, NV, Pre- and Post-Management Change.
42
-------
Figure 17 displays the suspended solids rating curves at the upper station established for the beginning
and ending periods of this study. A downward shift of the TSS rating curves indicates TSS became less
concentrated at higher flows after a change in management. At a discharge of 200 cfs, there was a
modeled 46% reduction in TSS concentrations between before and after. While flows greater than 200
cfs did occur during the later period, no TSS data where obtained during those times. Data for flows at or
below bankfull suggests no significant TSS or temporal difference in TSS.
Sediment Rating Curves @ Upper Station
1200
1000
800
.§ 600
At a Q of 200 cfs, there is a 46% reduction in total suspended solids
concentrations from the beginning of the evaluated period to the
end. Two percent of flows are at 200 cfs or above.
1990-1996
2000-2006
Best Fit Line, 1990-1996, R-squared = 0.9985
Best Fit Line, 2000-2006, R-squared = 0.9577
100
150
200 250
Discharge (CFS)
300
350
400
450
Figure 17. Sediment Rating Curves at Upper Station, Maggie Creek, NV.
43
-------
Prior to management change the TSS trend in 1994 was increasing but again was influenced by the
March, 1993 runoff event (Figure 18). TSS tended to slightly increase at the lower station after the
change in grazing management. However this may be largely flow related.
1 ?nn -
1 nnn -
onn
^
Sfinn
!2
K
Ann
~ynn
J-
TSS through Time @ Lower Station
+ 0
* 1990-1993
/ 0 1994-2006
/ o Irend94-0fa
/ 0 0
/ ° o
/ o o
* * ^i -ina^r ^^wfibM^i^teffl^^RLfljJH^. rftnQfo
90 J-92 J-94 J-96 J-98 J-00 J-02 J-04 J-06
Figure 18. TSS at Lower Station, Maggie Creek, NV, Pre- and Post-Management Change.
44
-------
Figure 19 demonstrates the same downward model shift at the lower station as the upper station (Figure
17). Again, a comparison of TSS concentrations at a flow of 200 cfs shows (Figure 19) a reduction of
about 47% over the time periods, which is similar to what was modeled at the upper station. Note also
what appears to be a threshold response around 125 cfs in the 1993-1999 point data, where small
increases in discharge seem to bring about large increases in TSS concentrations. This may be a signature
of the release of reservoir water into lower Maggie Creek, or of incision and discharge large enough to
contact gully banks above hydrophilic riparian vegetation. Below 50 cfs (approximately 90% of all
flows), there is little to no relationship between TSS and stream flow Q.
Sediment Rating Curves @ Lower Station
1200
1000
800
'ui
E 600
At a Qof 200 cfs, there is a 47% reduction in total suspended solids
concentrations from the beginning of the evaluated period to the
end. Two percent of flows are at 200 cfs or above.
1993-1999
0 2002-2008
Best Fit Line, 1993-1999, R-squared = 0.9387
Best Fit Line, 2002-2008, R-squared - 0.8975
100
200
300
400
Discharge (CFS)
500
600
700
800
Figure 19. Sediment Rating Curves at Lower Station, Maggie Creek, NV.
45
-------
The rating curves developed in Figures 17 and 19 used the limited data available to this study. Figure 20
depicts rating curves established using a substantially larger data set collected by Newmont. The figure
illustrates the need for large data sets to make simple, more accurate yearly comparisons. Note that the
2005 curve is highly influenced by only a couple of data points representing higher flows.
1993 Data
1993 Best Fit Line
200S Data
2005 Best Fit Line
DATE: 27 MARCH 06
MAGGIE CREEK
FLOW vs TSS - 1993 vs 2005
Figure 20. Rating Curves Developed by Newmont to Illustrate TSS Reductions through Time (from Simons et. al.
2009), Maggie Creek, NV.
46
-------
Orthophosphate Phosphorus (OP-P)
Dissolved OP-P values for all stations ranged from 0 to 1.6 mg/L with an average value of 0.13 mg/L
(Figure 21). The median value was 0.1 mg/L and the mode was 0 mg/L. The recommended maximum
level for rivers and streams is 0.1 mg/L (USEPA, 1986). Prior to management change, the trend in OP-P
concentration was influenced by the March, 1993 runoff event (Figure 21). After the change in grazing
management, OP-P tended to decrease (R2 = 0.30). No data were available at the upper station beyond
1999.
1 RD
J..OU
1 fin
J..OU
1 An
J-.H-U
1 ?n
±.zu
ST
-j 1 nn
^_ J..UU
M
n sn
Q_ U.OU
o
n fin
U.OU
0/in
.^U
09O
.zu
Onn
.uu
J-<
OP-P through Time @ Upper Station
1990-1993
0 1994-1999
Trend 90-93
Trend 94-99
^ o
O
* ^r p- ? o
+ST V *%°o o -X o-«-e>.?Q
* , o o "'b
90 J-92 J-94 J-96 J-98
Figure 21. OP-P Trend at Upper Station, Maggie Creek, NV, Pre- and Post-Management Change.
The average value of OP-P (mg/L) from 1990-1993 was 0.25 compared to 0.14 from 1996-1999, a 44%
reduction in concentrations (p = 0.18). The median value of OP-P during those same periods were 0.17
and 0.12 mg/L respectively, a 31% reduction (p = 0.14).
47
-------
OP-P has a relationship with TSS and discharge (Q), as seen in Figure 22. TSS and Q were strongly
related (Figure 17), especially at higher flows. Therefore, an OP-P discharge rating curve (Figure 23) was
developed using beginning and middle periods of the study (OP-P data from the upper station are not
available after 1999). There was a downward shift of the models, indicating OP-P becoming less
concentrated at higher flows between the two time periods. At a discharge of 200 cfs, there is a modeled
66% reduction in OP-P concentrations between the two periods. Flows greater than 216 cfs did not occur
during the middle time period.
OP-P vs Q, TSS @ Upper Station
a
/
//
//
/
//
/
o /
0 /
/ /'
hL^MSS'l D o
1000
Q
0 TSS
!
600 K Trend Q,R .qu 0.^
Trend TSS, R-squ=0.85
200
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80
OP (mg/L-P)
Figure 22. OP-P vs. Discharge and TSS at Upper Station, Maggie Creek, NV.
48
-------
1.80
1.60
1.40
s: L2°
i1-00
~ 0.80
OP-P Rating Curves @ Upper Station,
Beginning and Middle Periods
1990-1993
O 1996-1999
Trend 90-93, R-squ=0.98
Trend 96-99, R-squ=0.66
100
200 300
Q(cfs)
400
500
Figure 23. OP-P Rating Curves at Upper Station, Maggie Creek, NV, for Beginning and Middle Periods of the Study.
Both pre- and post-management change time periods exhibit declining trends in OP-P concentrations and
are not appreciably different (Figure 24). OP-P concentrations for beginning (1990-1993, R2 = 0.011) and
ending (2003-2006, R2 = 0.005) time periods were compared. At the lower stations, the mean value of
0.147 for the earlier time period was significantly higher than the later period value of 0.055 (p = 0.009),
indicating this location experienced a 63% reduction in mean phosphorus concentrations over time.
Comparison of median concentration values demonstrates a 93% reduction (p = 0.002).
49
-------
OP-P through Time @Lower Station
1.20
1.00
0.80
0.60
O.
o
0.40
0.20
0.00
1990-1993
o 1994-2006
Trend 90-93
Trend 94-06
* . * V^'rvO'XiP0^ S.
J-90 J-92 J-94 J-96 J-98 J-00 J-02 J-04 J-06
Figure 24. OP-P Concentration Trends for Two Periods at the Lower Station, Maggie Creek, NV.
A downward shift of the OP-P rating curve models for the lower station (Figure 25) indicates OP-P
becoming less concentrated at higher flows between the two time periods. At a discharge of 200 cfs,
there is a modeled 45% reduction in OP-P concentrations between the two periods. However, both
models are heavily influenced by one large event. In the early time period (1990-1993), prior to flow
augmentations from the reservoir, the upper station had 1.26 times the median phosphorus concentrations
of the lower station (p = 0.179). After this period (1994-1999), the upper station had about 2.25 times the
median OP-P concentration (p = 0.034), suggesting augmentation from reservoir releases may have been
diluting phosphorous concentrations by almost 80% during that time period.
50
-------
OP-P Rating Curves @ Lower Station, Beginning and
Ending Periods
0.40
0.35
0.30
ST 0.25
_j
^? 0.20
O 0.15
0.10
0.05
0.00
0.0
200.0
400.0
Q(cfs)
600.0
800.0
1990-1996
O 2000-2006
Trend 90-96, R-squ=0.24
Trend 00-06, R-squ=0.57
Figure 25. OP-P Rating Curves Displaying Lowering Trends at the Lower Station, Maggie Creek, NV.
51
-------
Over two year time intervals, there was a steady decline in OP-P concentrations at the upper station and a
general decline at the lower station with the exception of a spike in 1998/99 (Figure 26). This spike is not
exhibited at the upper station. OP-P concentrations are generally declining at both locations while
discharge is generally increasing (more obvious at the upper station), despite the positive relationship
between discharge and OP demonstrated in Figure 22. The variance of OP-P values between the 1990-93
and the 2003-06 periods are the same.
Median OP-P Concentrations and Flows at Upper and Lower
Station at 2-yr Intervals
OP, Lower
> OP, Upper
Q, Lower
Q, Upper
Period
Figure 26. Median OP-P Concentrations and Flows at Upper and Lower Stations, Maggie Creek, NV, Based on
Two-year Intervals.
52
-------
Nitrogen: Total (TN), Total Kjeldahl (TKN), and Nitrate + Nitrite (NOx)
Prior to 1994, the trend of both TN and NOx was sharply increasing at the lower station (R2 = 0.31 and
0.28, respectively) (Figure 27), representing a drought period that preceded a wet 1993. TKN is increased
(R2 = 0.01) at a slower rate. After grazing management changes in 1994, all nitrogen levels continued to
increase, but all at moderate to slower rates. During the post-management change, NOx was a much
smaller component of TN than before. Through time TKN contribute less, but still made up the majority
of TN throughout the entire post-management change period. The average value of NOx-N prior to
management change (1990-1993) was 0.25 mg/L, nearly 6.5 times the average between the years 2003-
2006 (p = 0.067).
Trends in Nitrogen Concentrations Pre- and Post-Management Change
at the Lower Station
4.00 -i
3.00 -
2.50 -
1.50 -
0.50 -
Year of change in livestock grazing strategies
TN
x TKN
NOx
Trend (TN)
Trend (TKN)
Trend (NOx)
J-90
J-92
J-94
J-96
J-98
J-00
J-02
J-04
J-06
Figure 27. Nitrogen Concentration Trends at the Lower Station, Maggie Creek, NV.
53
-------
Nitrogen data for the upper station is limited, consisting primarily of TKN data from 1991 through 1997
(n = 8, all R2 < 0.11). Figure 28 shows this data compared to the lower stations for the same period and
shows the upper station had slightly lower TKN concentrations compared to the lower station prior to
management change (p = 0.02), but had higher concentrations post-change (p = 0.19). The figure also
demonstrates the continued increasing trend in concentrations as seen at the lower station.
2.5 -
1.5
0.5
Trends in TKN Concentrations Pre- and Post-Management Change at
Upper and the Lower Station
Year of change in livestock grazing strategies
* Upper
O Lower
Trend (Upper)
Trend (Lower)
Figure 28. TKN Concentration Trends at Upper and Lower Stations, Maggie Creek, NV.
54
-------
Dissolved Oxygen (DO)
The concentration of DO over time at the lower station (Figure 29) shows an increasing trend pre-
management change (R2 = 0.32) and a slightly declining trend post management (R2 = 0.00). However,
the increase in the pre-management change period was primarily caused by low levels in the dry summer
of 1991. The average value for the years 1990-1993 was 8.5 while the average value for 2003-2006 was
9.5, indicating an insignificant (p = 0.152) increase of DO levels through the study period.
14
12
CIO
3
o
Q
DO Concentration Trends Pre- and Post-Management Change
at Lower Station
»-*»...*.
Trend (90-93)
Trend (94-06)
o
J-90 J-91 J-92 J-93 J-94 J-95 J-96 J-97 J-98 J-99 J-00 J-01 J-02 J-03 J-04 J-05 J-06
Figure 29. DO Concentration Trend at Lower Station, Maggie Creek, NV, Pre- and Post-Management Change.
55
-------
The DO concentration overtime at the upper station (Figure 30) increased during both pre- and post-
management change. However the increase in the pre-management change period was primarily caused
by low levels in the dry summer of 1991. The average value for the years 1990-1993 was 6.9 mg/L while
the average value for 2003-2006 was significantly higher (p = 0.030) at 9.7 mg/L.
14
12
I
O 6
Q
DO Concentration Trends Pre- and Post-Management Change
at Upper Station
Trend (90-93)
Trend (94-06)
J-90 J-91 J-92 J-93 J-94 J-95 J-96 J-97 J-98 J-99 J-00 J-01 J-02 J-03 J-04 J-05 J-06
Figure 30. DO Concentration Trend at the Upper Station, Maggie Creek, NV, Pre- and Post-Management Change.
56
-------
Water Temperature
The yearly average air temperature recorded at Elko, NV for the period of study displays a trend of
increasing temperature (R2 = 0.27) that appears to be heavily influenced by one early low (1993) and
three later high readings in 2001, 2003, and 2006 (Figure 31).
10.0 -i
9.5 -
8.0 -
I "
7.0 -
6.5 -
6.0 -
5.5 -
5.0
Yearly Average Air Temperature Trend, Elko, NV
-Trendline
1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008
Figure 31. Yearly Average Air Temperature Trend at Elko, NV, 1990 - 2006.
57
-------
Water temperature measurement at the upper station was very limited. In some cases the yearly average
was based on one or two measurements. At the lower station, increasing water temperature (R2 = 0.02)
(Figure 32) reflects increasing air temperatures at Elko, while the upper station temperature increased
more quickly (R2 = 0.12). The average water temperature at the lower station averaged about 2.2° C
higher than at the upper station for all data collected during the study period (p = 0.053).
Yearly Average Water Temperature Trend at Upper and Lower Station
23.0 n
21.0 -
19.0 -
17.0 -
-15.0
Q.
13.0 -
11.0 -
7.0 -
5.0
Upper
o Lower
Trend (Upper)
Trend (Lower)
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
Figure 32. Yearly Average Water Temperature Trend at Upper and Lower Stations, Maggie Creek, NV.
Discussion
Figure 16 does not show a water quality issue related to TSS, yet occasionally TSS is high presumably
during very high flow events. These events may indicate the ability of the stream to handle big events
and maintain its functions. The water quality standards approach is not likely to address the more
important question of whether TSS or sediment in general is related to what motivates water quality
standards. For fish habitat, for example, spawning gravels can become clogged and the complexity of the
aquatic food web can be diminished if habitat becomes less diverse and complex due to the force of big
events when not dissipated and to the physical effects of sediment in altering habitats.
With no negative answers for "upland watershed contributing to riparian degradation" (attribute 5), it is
clear that sources of sediment and pollutants are primarily the riparian ecosystem itself rather than
external sources. Of the functional groups of attributes (hydrologic, vegetation, and soils) evaluated in a
PFC assessment, the vegetation group responds most quickly to and is most immediately affected by
58
-------
management change. While each functional group is intertwined with the other (a functionality triangle
or the "three-legged stool concept"), a functional vegetation community is crucial for riparian repair and
maintenance. The vegetation response due to the change in grazing strategy on Maggie Creek during the
time of this study has been addressed by Simonds et al. (2009). Some of their key findings include:
Substantial recovery of riparian vegetation as a consequence of changes in livestock
management.
138% increase in riparian vegetation acreage within all prescribed grazing pastures, 1994 vs.
2006 via (CIR) analysis.
114% increase in riparian vegetation acreage of Maggie Creek Watershed Restoration Project
(MCWRP) reaches, 1994 vs. 2006 (CIR).
Riparian recovery leading to elevated and more stable water tables.
Well data in relation to precipitation, elevation, stream order, grazing use, and changes in
riparian vegetation data suggest increased well elevations are correlated with increased
vegetation beyond ambient influences.
Percent of riparian vegetation in relation to the potential riparian area on Beaver Creek
riparian pasture increased from 34% in 2001 to 85% in 2006 (Landsat analysis).
Other geomorphic features related to PFC and aquatic habitats have been measured/evaluated by Simonds
et al. (2009) and Evans (2009) including:
54% decrease in water acreage of MCWRP reaches, 1994 vs. 2006, CIR analysis (indication
of narrowing channels, especially in light of the following...).
7% increase in stream length of MCWRP reaches, 1994 vs. 2006, CIR analysis (indication of
increased sinuosity, which aids in energy dissipation and increased water storage capacity).
54% decrease in gravel acreage of MCWRP reaches, 1994 vs. 2006, CIR analysis.
Stream width to depth ratios decreased in all important LCT reaches monitored (1994 or 1996
to 2006).
Woody riparian vegetation overhang generally tends toward increasing over time, but 2006
shows a decline likely due to the smothering by gravels from the 2006 flooding.
Average number of quality pools has increased, with data starting from 1996. Quality pools
are deeper and have more fish hiding cover.
Limited hydrophytic plant cover data collected in 2006 by BLM and photos appear to support
a wetter system than before.
Streams generally show an improvement in PFC with the exception of the Lower Simon
Creek Parcel (grazing practices questioned) and areas impacted by 2006 flooding.
While 2006 flooding may have reduced the functionality ratings, riparian characteristics were
effective at dissipating energy and capturing sediment, indicating that the riparian zone was
functioning during a high flow event to maintain functions.
Comparisons to survey data prior to 1994 indicate that riparian conditions have increased
dramatically, with a substantial increase in riparian condition class, decrease in width to depth
ratios, and increase in percent pool quality.
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Beaver activity has increased substantially, creating high quality pool habitat, especially in
Maggie Creek.
These findings are consistent with and expected by the PFC assessments of this study. Two hydrologic,
four vegetation, and two soil PFC attributes were found to have improved in over 10% of stream miles
assessed, contributing to an overall improvement in the functional ratings of the reaches. These
improvements lead to the general hypothesis that all water quality parameters examined would show an
improving trend, especially at the upper station. The only attribute that declined over total stream miles
(by less than 10%) was attribute 17 (stream is in balance with the water and sediment being supplied by
the watershed). This was due to the excessive gravel loads that were moved during the 2006 floods.
These gravels suggest that all reaches in the watershed and item 5 (upland watershed contributing to
riparian degradation) may be relevant to functionality, even if reaches isolated by downstream ephemeral
reaches are not relevant to water quality at monitoring stations.
Improved base flows (i.e., higher flows, increased duration) were predicted. Improvement was the case
for the lower station, but may not have been for the upper station. As mentioned in the results, this may
be due to mine dewatering activities that were in proximity to the upper station that discharged mine
water back into Maggie Creek between the two stations. Baseflow is also influenced by the cycle of
above average and below average precipitation, which occurred during the time period of this study.
Furthermore, various water diversions in both the mid and lower watershed confound flow and
groundwater recharge dynamics, making it difficult to determine if improvements were realized even
without mine dewatering. A more detailed hydrologic study focused on the mid-basin where land
management changes were implemented is needed to answer base flow questions; however, Simonds et
al. (2009) did find evidence of increased well water elevations which, if sufficient, might help enhance
future base-flow conditions.
Reductions in TSS were predicted and realized. Sediment rating curves for both stations indicated similar
reductions in sediment transport, while it was hypothesized the lower stations should have less reduction.
Simonds et al. (2009) cite a 2005 Newmont report that used an independent data set to determine a 10-
fold decrease in sediment loads on Maggie Creek between 1993 and 2005 (Figure 20), although the
specific location of data collection is unclear in the Newmont report. Other water quality issues are
related to sediment (e.g., nutrients), and sediment is itself a chief pollutant of concern. There were no
known upland land management changes which would have changed sediment delivery to the stream
system. In fact, three fires occurred within the watershed during the period of this study. Bare, unstable
banks persisted prior to the study. They became vegetated with enough of the appropriate riparian plant
communities to not only reduce sediment delivery from bank erosion, but to effectively filter any fire
induced sediment. This is a strong case for managing toward proper functioning condition.
Reductions in nutrients (P and N) were predicted. The results for this hypothesis were somewhat mixed,
which is not surprising given the complex dynamics of nutrient cycling. It is expected that as plant
communities expanded, nutrients would be taken up to meet growth needs and be filtered/processed by
the expanded riparian width. It is also anticipated that litter material would become a source of nutrients
eventually. However, it is thought the pace of uptake will be high enough to offset decomposition during
this period of increasing riparian biomass and complexity.
Phosphorus, being highly associated with sediment, was expected to decline. This was the case for OP-P
at both stations. Reductions in concentrations were found to be greater at the lower stations. Flow
augmentations from the reservoir were likely diluting OP-P concentrations at the lower station,
confounding hypothesis testing. Phosphorus release is expected during reducing conditions, which the
majority of this system was clearly not experiencing during this time. Increased water oxygen levels
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coupled with increasing nitrate levels (addressed below) supports the assumption that Maggie Creek
system was not dominated by a reducing environment. As the riparian systems continue to expand, a more
reducing environment may eventually dominate. However, such an environment engages more effective
sediment deposition on floodplains and more plant growth with nutrient uptake.
Phosphorus appeared to be effectively trapped and taken up by the riparian community during the time of
this study. Total phosphorus is a nutrient of concern on Maggie Creek, being listed on the 2006 303(d)
list as having a low TMDL priority. Continued decline in phosphorus could lead to delisting due to
improved riparian functionality.
Nitrogen data are limited at the upper station, with only a few TKN values over a short time span to
compare to the lower station. These data demonstrate comparably lower TKN concentrations prior to
management change with indication of increasing trends. Post-management change saw continued
increasing trends, but a considerable increase in concentration at the upper station. This is likely the
result of increased organic litter accumulation due to increased riparian plant communities just upstream
from the upper station.
The lower station had more nitrogen data than the upper station. Prior to management changes, TN was
on a sharply increasing trend, driven mostly by increases in NOx in 1993. NOx may accumulate during
drought and then be flushed in high water flows, especially if the flows come from uplands and precede
the growing season. TKN is relatively low and barely exhibits an increasing trend. This indicates
possible nitrogen sources other than vegetation. After management change, trend of all nitrogen forms
leveled to slightly increasing, with the bulk of TN made up of TKN at the beginning. As the trend
continues, TKN still makes the majority of TN, but progressively gives way to greater concentrations of
NOx. This suggests that plant matter became the primary source of nitrogen in the system, and
accumulating organic nitrogen from leaf litter was gradually starting to convert to nitrate/nitrite especially
in more oxygenated conditions upstream. If functionality increases and anoxic conditions prevail,
nitrogen will be sequestered in the riparian zone. A fluctuating high water table with available organic
material (e.g., from roots) facilitates denitrification.
Dissolved Oxygen (DO) was predicted to increase. This was the case for the overall data and upper
station. At both the upper and lower stations, pre-management change trends were rapidly increasing due
to very low DO levels recorded in 1991. The post-management period demonstrated an increasing trend
at the upper station, a decreasing one for the lower station, though both rates are much less radical than
pre-management. That the lower station was trending down is not surprising. Any oxygen gains realized
in the upper reaches would surely be diminished by the poorly functioning lower riparian reaches coupled
with the augmentation of warm, relatively oxygen-poor reservoir water.
Water temperature was predicted to decrease. Water temperature is highly variable in general, fluctuating
on a diel and seasonal basis, as well as being affected by variations in local shading, channel morphology,
and ground water-surface water or hyporheic interactions. It is therefore unrealistic to expect meaningful
trends in water temperature data collected at most once every four months (the upper station was not
collected nearly as often) at a location that is outside the influence of management change. The results of
yearly average air and water temperature comparisons shows the lower station exhibited an increasing
water temperature trend not too unlike that of the air with just a slightly lower slope. This would be
expected as water from the reservoir is fully exposed to the atmosphere (Smith and Lavis (1975). Crisp
and Howson (1982) and Mackey and Berrie (1991) showed that surface water temperature is closely
related to air temperatures across a range of catchment types and sizes, but water has a higher thermal
capacity. Trend for the upper station demonstrated a markedly increased trend toward warmer
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temperatures, but variance between the later years was high due to missing quarterly data. In summary,
little can be determined about the water temperature trend within the managed area with the data
available.
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63
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Conclusion
Rather than implement a sampling design tailored to address the specific hypotheses (realized to be an
excessively expensive approach), this retrospective study was based on currently available data, which
limited the ability to sufficiently address hypothesis questions. To address this challenge, we sought and
used a watershed with (relatively) extensive data, far more than generally available to managers of land
and water quality.
Even though water quality data for this watershed were dense in comparison to other watersheds for
which the study questions could be asked, they were inadequate. The sediment rating curves suggested a
difference between before and after the change in management, but the change in functionality was based
on four points. One point was near the origin of the graph and represented base flow conditions. The
other three points represented higher flows that were great enough to transport sediment (two before and
one after). Many other graphs and statistical relationships (e.g., nitrogen and phosphorous especially,
Figs. 21-28) appeared to be driven by spacial data points representing high or low flows. Because the
Nevada Division of Environmental Protection protocol states that data from floods and droughts should
not be used to evaluate whether water quality standards are being met these special conditions are deemed
inappropriate for basing impairment decisions. Therefore, one is left to use average flow data even
though these conditions may not be critical for the beneficial use. It is during drought and seasonal low
flows when fish populations generally suffer.
Interestingly, during dry periods riparian vegetation can help a stream recover by growing toward the
remaining water. Subsequently, in wetter periods, vegetation is available to capture sediment, build
banks, and narrow the channel width. Much stream habitat rebuilding occurs during floods if a stream
has floodplain available for energy dissipation and vegetation in place for stabilizing banks and providing
resistance to scouring flows.
In the Maggie Creek Watershed, the stream flows through three or four sequences of channel incision and
recovery through gully widening. This is probably the major source of sediment (and nutrients or
pollutants) in a watershed without upland watershed conditions that lead to riparian degradation. Thus,
TSS data do not provide useful information to address the very reasons why monitoring data are collected
and used to manage water quality. Furthermore, these data are so expensive ($300-500 for lab fees plus
labor and travel expenses to collect the sample per sampling event at one location), that they can be
collected only at infrequent locations that represent large watersheds. This watershed contained almost
one hundred reaches that were presumed to be relevant to these water quality data and hundreds more
where water quality and aquatic habitats are important to organisms and important to people. Lahontan
Cutthroat Trout (LCT) live in some of the tributary streams that were not addressed by this study because
the intervening reaches were ephemeral. Yet this large watershed had water quality data from only two
locations and only quarterly.
A far better approach to monitoring for water quality management is to monitor the drivers (leading
indicators) rather than the lagging response indicator of water quality. The driving functions provide
insight to the variables that should be the focus for monitoring and management. For water quality in
rangeland or most other wildland aquatic habitats, riparian PFC focuses attention on those attributes
useful for quantitative monitoring (see introduction). An example of using these functions for focused
monitoring is packaged in the Multiple Indicator Monitoring protocol (Burton et al. 2011). This was
developed to quantitatively monitor fish habitat and focuses most attention on the conditions of riparian
vegetation as it relates to bank stability. To apply Multiple Indicator Monitoring or any other quantitative
monitoring method, it is first important to identify functional-at-risk downward trending reaches where a
management change is needed or has recently been implemented. The PFC items discussed above
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provide insight to needed changes and help set good objectives. Good objectives should be specific,
measureable, achievable, related to management and riparian functions, and valued by stakeholders. Since
riparian conditions often depend on vegetation and the riparian management that drives these changes,
riparian and water quality concerns should often focus on measuring vegetation change (e.g., Winward
2000 or Burton etal. 2011).
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References
Addiscott, T. 1997. A critical review of the value of buffer zone environments as a pollution control tool.
In: Haycock, N., Burt, T., Goulding, K., and Pinay, G. (eds.). Buffer zones: their processes and
potential in water protection. The Proceedings of the International Conference on Buffer zones,
September 1996. Electronic version, Haycock Associated Limited, St. Albans, Hertfordshire, UK.
326 pp.
Barnes, J.R., and Minshall, G.W. [Eds.]. 1983. Stream ecology: application and testing of general
ecological theory. Plenum Press, New York and London. 399 p.
Beschta, R.L. 1984. TEIMP-85; A computer model for predicting stream temperatures resulting from the
management of stream-side vegetation. USDA Forest Service, Watershed Systems Development
Group, Ft. Collins, Colorado. WSDG-AD-00009, 76 pp.
Bilotta, G. and Brazier, R. 2008. Understanding the influence of suspended solids on water quality and
aquatic biota. Water Research, 42, 2849-2861.
Blackport, R., MacGregor, R., and Imhof, J. 1995. An approach to the management ofgroundwater
resources to protect and enhance fish habitat. Canadian Manuscript Report of Fisheries and Aquatic
Sciences, no. 2284.
BLM (Bureau of Land Management). 1993. Final Environmental Impact Statement, Newmont Gold
Company's South Operations Area Project. Elko District, Elko, Nevada. Internal report, including
Appendix A, Mitigation Plan.
BLM (Bureau of Land Management). 2001. Public land statistics 2000. Volume 185, BLM/BC/ST-
01/001+1165. (http://www.blm.gov/natacq/plsOO/). Accessed April, 2011.
Broadfoot, W. and Williston, H. 1973. Flooding effects on southern forests. Journal of Forestry, 71,
584-587.
Brown, G. and Krygier, J. 1970. Effects of clear-cutting on stream temperature. Water Resources
Research 6, 1133-1139.
Bryce, S.A., Woods, A.J., Morefield, J.D., Omernik, J.M., McKay, T.R., Bracklry, O.K., Hall, R.K.,
Higgins, O.K., McMorran, B.C., Vargas, K.E., Petersen, E.B., Zamudio, B.C., and Comstock, J.A.
2003. Ecoregions of Nevada (color poster with map, descriptive text, summary tables, and
photographs): Reston, VA. US Geological Survey (map scale 1:1,350,000).
Burchsted, B., Baniels, M., Thorson, R., and Vokoun, J. 2010. The river discontinuum: applying beaver
modifications to baseline conditions for restoration for forested headwaters. BiosScience, 60 (11),
908-922.
Burton, T., Smith, S., and Crowley, E. 2011. Multiple indicator monitoring (MIM) of stream channels
and streamside vegetation. Bureau of Land Management, Technical Reference 1737-23. 155pp.
Bush, J. and Van Auken, O. 1984. Woody species composition of the upper San Antonio River gallery
forest. Texas Journal of Science, 36, 139-148.
66
-------
Caissie, D. 1991. The importance of groundwater to fish habitat: base flow characteristics for three Gulf
Region Rivers. Canadian Data Report of Fisheries and Aquatic Sciences, no. 814.
Castelle, A., Johnson, A., and Conolly, C. 1994. Wetland and stream buffer size requirements. Journal
of Environmental Quality, 23(5), 878-882.
Clemmer, P. 1994 (Revised 2001). Riparian area management: The use of aerial photography to manage
riparian-wetland areas. USDI BLM Technical Reference 1737-10, 55 pp.
Cooper, J., Gilliam, J., Daniels, R., and Robarge, W. 1987. Riparian areas as filters for agricultural
sediment. Soil Science Society of America Journal, 51(2), 416-420.
Correll, D., Jordan, T., and Weller, D. 1996. Failure of agricultural riparian buffers to protect surface
waters from groundwater contamination. In: Gilbert, J. (Ed.) Groundwater-Surface Water Ecotones.
Cambridge Univ. Press, London.
Correll, D. 1997. Buffer zones and water quality protection: general principles. In: Haycock, N., Burt,
T., Goulding, K., and Pinay, G. (eds.). Buffer zones: their processes and potential in water protection.
The Proceedings of the International Conference on Buffer zones, September 1996. Electronic
version, Haycock Associated Limited, St. Albans, Hertfordshire, UK. 326 pp.
Correll, D., Jordan, T., and Weller, D. 2000. Beaver pond biogeochemical effects in the Maryland
coastal plain. Biogeochemistry, 49(3), 217-239.
Crisp, D. and Howson, G. 1982. Effect of air temperature upon mean water temperature in streams in
the north Pennines and English Lake District. Freshwater Biology, 12, 359-367.
Cunjak, R. and Power, G. 1986. Winter habitat utilization by stream resident brook trout (Salvelinus
fontinalis) and brown trout (Salmo trutta). Canadian Journal of Fisheries and Aquatic Sciences 43,
1970-1981.
Davies-Colley, R.J. 1997. Stream channels are narrower in pasture than in forest, New Zealand Journal
of Marine and Freshwater Research, 31:5, 599-608.
Demmer, R. and Beschta, R. 2008. Recent history (1988-2004) of beaver dams along Bridge Creek in
central Oregon. Northwest Science, 82:4, 309-318.
Dillahalll, T., and Inamdar, S. 1997. Buffer zones as sediment traps or sources. In: Haycock, N., Burt,
T., Goulding, K., and Pinay, G. (eds.). Buffer zones: their processes and potential in water
protection. The Proceedings of the International Conference on Buffer zones, September 1996.
Electronic version, Haycock Associated Limited, St. Albans, Hertfordshire, UK. 326 pp.
Dunne, T. and Leopold, L.B. 1978. Water in Environmental Planning. Freeman, New York. 818 pp.
Evans, C. 2009. Maggie Creek watershed restoration project 1993 south operations area project
mitigation plan: 2006 monitoring summary and evaluation of biological standards. Elko District,
Bureau of Land Management. Internal report.
Freeze, R. and Cherry, J. 1979. Groundwater. Englewood Cliffs, New Jersey: Prentice-hall.
67
-------
Gebhardt, K., Gohn, C., Jensen, S., and Platts, W.S. 1989. Use of hydrology in riparian classification.
In Practical Approaches to Riparian resource Management-An Educational Workshop. Bureau of
Land Management. Billings, MT. pp. 53-59.
Gebhardt, K., Leonard, S., Staidl, G., and Prichard, D. 1990. Riparian area management: riparian and
wetland classification review. USDI BLM TR 1737-5. 56 pp.
Gilliam, J. 1994. Riparian wetlands and water quality. Journal of Environmental Quality, 23(5), 896-
900.
Gilliam, J., Parsons, J., and Mikkelsen, R. 1997. Nitrogen dynamics in buffer zones. In: Haycock, N.,
Burt, T., Goulding, K., and Pinay, G. (eds.). Buffer zones: their processes and potential in water
protection. The Proceedings of the International Conference on Buffer zones, September 1996.
Electronic version, Haycock Associated Limited, St. Albans, Hertfordshire, UK. 326 pp.
Ghermandi, A., Vandenberghe, V., Benedetti, L., Bauwens, W., and Vanrolleghem, P. 2009. Model-
based assessment of shading effect by riparian vegetation on river water quality. Ecological
Engineering, 35, 92-104.
Girel, J. and Pautou, G. 1997. The influence of sedimentation on vegetation structure. In: Haycock, N.,
Burt, T., Goulding, K., and Pinay G. (eds.). Buffer zones: their processes and potential in water
protection. The Proceedings of the International Conference on Buffer zones, September 1996.
Electronic version, Haycock Associated Limited, St. Albans, Hertfordshire, UK. 326 pp.
Groffman, P., Axelrod, E., Lemunyon, J., and Sullivan, W. 1991. Denitrification in grass and forest
vegetated filter strips. Journal of Environmental Quality, 20, 671-674.
Hare, L., Heggem D., Hall R., and Husby P. An Ecological Characterization and Landscape Assessment
of the Humboldt River Basin. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-
13/006, January, 2013.
Hare, L., Heggem D., Hall R., and Husby P. Ecological Condition of Streams in Northern Nevada EPA
R-MAP Humboldt Basin Project. U.S. Environmental Protection Agency, Washington, DC,
EPA/600/R-12/605, August, 2012.
Hall, R., Watkins, R., Heggem, D., Jones, B., Kaufmann, P., Moore, S., and Gregory, S., Quantifying
Structural Physical Habitat Attributes Using Lidar and Hyperspectral Imagery; Journal of
Environmental Monitoring and Assessment. Journal of Environmental Monitoring and Assessment,
published online, January, 2009.
Haycock, N. and Burt, T. 1993. Role offloodplain sediments in reducing the nitrate concentration of
subsurface runoff: a case study in the Cotswolds, UK. Hydrological Processes, 7, 287-295.
Haycock, N. and Pinay, G. 1993. Groundwater nitrate dynamics in grass and poplar vegetated riparian
buffer strips during the winter. Journal of Environmental Quality, 22, 273-278.
Hill, A. 1997. The potential role of riparian forests as buffer zones. In: Haycock, N., Burt, T., Goulding,
K., and Pinay, G. (eds.). Buffer zones: their processes and potential in water protection. The
Proceedings of the International Conference on Buffer Zones, September 1996. Electronic version,
Haycock Associated Limited, St. Albans, Hertfordshire, UK. 326 pp.
68
-------
Homer, C., Dewitz, J., Coan, M., Hossain, N., Larson, C., Herold, N., McKerrow, A., VanDriel, J.N., and
Wickham, J. (2007). Completion of the 2001 National Land Cover Database for the Conterminous
United States. Photogrammetric Engineering and Remote Sensing, Vol. 73, No. 4, pp 337-341.
Hupp, C. and Osterkamp, W. 1985. Bottomland vegetation distribution along Passage Creek, Virginia in
relation to fluvial landforms. Ecology, 66, 670-681.
Jensen, S., Ryel, R., and Platts, W. 1989. Classification of riverine/riparian habitat and assessment of
nonpoint source impacts, North Fork Humboldt River Nevada. Report to USDA Forest Service,
Intermountain Research Station. White Horse Associates, Smithfield, UT. 165 pp.
Jordan, T., Correll, D., and Weller, D. 1993. Nutrient interception by a riparian forest receiving inputs
from adjacent cropland. Journal of Environmental Quality, 22:3, 467-473.
Kaushal, S., Groffman, P., Mayer, P., Striz, E., and Gold, A. 2008. Effects of stream restoration on
denitrification in an urbanizing watershed. Ecological Applications, 18: 789-804.
Klotz, R. 2010. Reduction of high nitrate concentrations in a central New York state stream impounded
by beaver. Northeastern Naturalist, 17:3,349-356.
Kormondy, E. 1969. Concepts of ecology. Prentice-Hall, Inc., Englewood Cliffs, New Jersey. 209pp.
Kozlowski, D. 2007. Pre-fire functional condition and post-fire channel changes in northern Nevada
streams: the 1999-2001 fires [thesis]. Reno, NV, USA: University of Nevada. 180 pp.
Kozlowski, T. 1984. Responses of woody plants to flooding. In: Kozlowski, T. (Ed.) Flooding and plant
Growth. Orlando, Academic Press, pp 129-163.
Lane, E. W. 1955. The importance of fluvial morphology in hydraulic engineering. American Society of
Civil Engineering, Proceedings, 81, paper 745:1-17.
Leonard, S., Staidl, G., Fogg, J., Gebhardt, K., Hagenbuck, W., and Prichard, D. 1992. Procedures for
ecological site inventory - with special reference to riparian-wetland sites. U.S. Department of the
Interior Bureau of Land Management, Technical Reference 1737-7.
Leopold, L.B. 1994. A view of the river. Harvard University Press, Cambridge, Massachusetts. 298pp.
Leopold, L. B., Wolman, M.G., and Miller, J. P., 1964. Fluvial processes in geomorphology. Freeman
Co., San Francisco, California, 522 pp.
Lowrance et al. 1995. Water quality functions of riparian forest buffer systems in the Chesapeake Bay
watershed. Report No. EPA 903-R-95-004. U.S. Environmental Protection Agency, Washington,
D.C.
Mackey A. and Berrie, A. 1991. The prediction of water temperatures in chalk streams from air
temperatures. Hydrobiologia, 210, 183-189.
Malcolm, I., Hannah, D., Donaghy, M., Soulsby, C., and Youngson, A. 2004. The influence of riparian
woodland on the spatial and temporal variability of stream water temperatures in an upland salmon
stream. Hydrology and Earth System Sciences, 8(3), 449-459.
69
-------
Mander, U., Matt, O., and Nugin, U. 1991. Perspectives on vegetated shoals, ponds and ditches as
extensive outdoor systems ofwastewater treatment in Estonia. In: Etnier, C. and B. Guterstam (Eds.)
Ecological engineering for wastewater treatment. Proceedings of the International Conference at
Stensund Folk College, Sweden, pp. 271-282.
Mann, C.C. 2005. 1491 - New Revelations of the Americas before Columbus. Vintage Books of Random
House, New York, 541 pp.
Manning, M., Swanson, S., Svejcar, T., and Trent, J. 1989. Rooting characteristics of four intermountain
meadow community types. Journal of Range Management, 42(4), 309-312.
Manning, M.E. and Padgett, W.G. 1995. Riparian community type classification for Humboldt and
Toiyabe National Forests, Nevada, and Eastern California. USDA Forest Service, Intermountain
Region, R4-Ecol-95-01. 306 pp.
Maret, T., Parker, M., and Fannin, T. 1987. The effect of beaver ponds on the nonpoint source water
quality of a stream in southwestern Wyoming. Water Resources, 21(3), 263-268.
Margolis, B., Castro, M., and Raesly, R. 2001. The impact of beaver impoundments on the water
chemistry of two Appalachian streams. Canadian Journal of Fisheries and Aquatic Sciences, 58,
2271-2283.
Marti, E. and Sabater, F. 1996. High varaiability in temporal and spatial nutrient retention in
Mediterranean streams. Ecology, 77(3), 854-869.
Mayer, P., Reynolds, S., McCutchen, M., and Canfield, T. 2005. Riparian buffer width, vegetative cover,
and nitrogen removal effectiveness: a review of current science and regulations. Washington, DC:
US Environmental Protection Agency. EPA/600/R-05/118.
Meador, M. and Goldstein, R. 2003. Assessing water quality at large geographic scales: relations
among land use, water physicochemistry, riparian condition, and fish community structure.
Environment Management, 31(4), 504-517.
Miller, J.R., House, K., Germanoski, D., Tausch, R.J., and Chambers, J.C. 2004. Fluvial geomorphic
responses to Holocene climate change. In: Chambers, J.C. and J.R. Miller (Eds.), Great Basin riparian
ecosystems: ecology, management, and restoration. Island Press, 1718 Connecticut Ave. NW, Suite
300, Washington, D.C., 20009, pp.49-87.
Montgomery, D. and Buffington, J.M., 1993. Channel classification, prediction of response and
assessment of channel condition. Washington State Timber, Fish, and Wildlife TFW-SH10-93-002,
104pp.
Myers, L. 1989. Riparian area management: inventory and monitoring of riparian areas. TR 1737-3.
Bureau of Land Management, BLM/YA/PT-89/022+1737, Service Center, CO. 89 pp.
Naiman, R., Pinay, G., Johnston, C., and Pastor, J. 1994. Beaver influences on the long-term
biogeochemical characteristics of boreal forest drainage networks. Ecology, 75(4), 905-921.
Osbourne, L. and Kovacic, D. 1993. Riparian vegetated buffer strips in water quality restorations and
stream management. Freshwater Biology, 29, 243-258.
70
-------
Parsons, J., Daniels, R., Gilliam, J., and Dillaha, T. 1994. Reduction in sediment and chemical load in
agricultural field runoff by vegetative filter strips. Report No. UNC-WWRI-94-286, Water
Resources Res. Inst, Raleigh, NC, 45 pp.
Peterjohn, W. and Correll, D. 1984. Nutrient dynamics in an agricultural watershed: observations on
the role of a riparian forest. Ecology, 65, 1466-1475.
Peterjohn, W. and Correll, D. 1986. The effect of riparian forest on the volume and chemical
composition ofbaseflow in an agricultural watershed. In: Correll, D. (Ed.), Watershed Research
Perspectives, Smithsonian Press, Washington, B.C. pp. 244-262.
Power, G., Brown, R., and Imhof, J. 1999. Groundwater and fish: insights from northern North
America. Hydrological Processes, 13,401-422.
Prichard, D., Anderson, J., Correll, C., Fogg, J., Gebhardt, K., Krapf, R., Leonard, S., Mitchell, B., and
Staats, J. 1998. Riparian Area Management: A User Guide to Assessing Proper Functioning
Condition and Supporting Science for Lotic Areas. USDI BLM, USDA FS and NRCS Technical
Reference 1737-15, 126pp.
Prichard, D., Barrett, H., Cagney, J., Clark, R, Fogg, J., Gebhardt, K., Hansen, P.L., Mitchell, B., and
Tippy, D. 1993 (and 1995). Riparian Are a Management: Process for Assessing Proper Functioning
Condition. USDI BLM, USDA FS and NRCS Technical Reference 1737-9, 52 pp.
Reed, P., Jr. 1988. National list of plant species that occur in wetlands: intermountain (region 8).
Biological Report 88(26.8), USDI Fish and Wildlife Service, Fort Collins, CO. 76 pp.
Rosgen, D. 1996. Applied River Morphology. Wildland Hydrology, Pagosa Spings, CO.
Rosgen, D. 2006. Watershed Assessment of River Stability and Sediment Supply (WARSSS). Wildland
hydrology, Ft. Collins, CO.
Schumm, S.A. 1979. Geomorphic thresholds: the concept and its applications. Transactions of the
Institute of British Geographers, 4(4):485-515.
Schumm, S.A., Harvey, M.D., and Watson, C.C. 1984. Incised channels: Morphology, dynamics and
control. Water Resources Publications, Littleton, CO.
Simonds, G., Ritchie, M., and Sant, E. 2009. Evaluating riparian condition and trend in three large
watersheds. Open Range Consulting,
http://www.openrangeconsulting.com/watershed/watershed_report.pdf Accessed April, 2011.
Strahler, A.N. 1964. Geology Part II. Quantitative Geomorphology of Drainage Basins and Channel
Networks. Section 4-II In: Chow (Ed in Chief), Handbook of Applied Hydrology McGraw-Hill, New
York 4-39 to 4-76.
Sinokrot, B. and Stefan, H. 1993. Stream temperature dynamics: measurements and modeling. Water
Resources Research, 29(7), 2299-2312.
Smith, C. 1989. Riparian pasture retirement effects on sediment, phosphorus and nitrogen in
channelized surface runoff from pastures. New Zealand Journal of Marine and Freshwater
Resources, 23, 139-146.
71
-------
Smith, K. and Lavis, M. 1975. Environmental influences on the temperature of a small upland stream.
Oikos, 26, 228-236.
State of Nevada. 2011. Directory of Nevada Mine Operations, January-December, 2010. Department of
Business & Industry, Division of Industrial Relations (http://dirweb.state .nv.us.) Accessed March 16,
2012.
Sweeney, B., Bott, T., Jackson, J., Kaplan, L., Newbold, J., Standley, L., Hession, W., and Horwitz, R.
2004. Riparian deforestation, stream narrowing, and loss of stream ecosystem services. Proceedings
of the National Academy of Sciences, 101(39), 14132-14137.
Tabacchi, E., Lambs, L., Guilloy, H., Planty-Tabacchi, A., Muller, E., and Decamps, H. 2000. Impacts
of riparian vegetation on hydrological processes. Hydrological Processes, 14, 2959-2976.
Theurer, F., Voos, K., and Miller, W. 1984. Instrearn water temperature model. Instream Flow
Information Paper 16, U.S. Fish and Wildlife Service, Washington, D.C.
USEPA. 1986. Quality Criteria for Water. U.S. Environmental Protection Agency, EPA#440/5-86-001.
USEPA. 1988. Dissolved Oxygen Water Quality Standards Criteria Summaries: A Compilation of
State/Federal Criteria. EPA # 440/5-88-024, September.
USEPA. 2009. The National Water Quality Inventory: Report to Congress for the 2004 Reporting Cycle,
Office of Water, EPA 841-F-08-003, January.
USEPA. 2012. FY 2013 EPA Budget in Brief. United States Environmental Protection Agency, Office of
the Chief Financial Officer (2710A), Publication Number: EPA-190-S-12-001. February 2012.
USFS. 1992. Integrated riparian evaluation guide-Intermountain Region. USDA Forest Service,
Intermountain Region, Ogden, UT. 199 pp.
USGS. 2012. The United States Department of the Interior Budget Justification and Performance
Information, FY 2013, U.S. Geological Society.
http://www.usgs.gov/budget/2013/greenbook/FY 2013 USGS.pdf Accessed April 5, 2012.
Uusi-Kamppa, J. and Ylaranta, T. 1996. Effect of buffer strips on controlling soil erosion and nutrient
losses in southern Finland. In: Mulamoottil, G., B. Warner, and E. McBean (Eds.) Wetlands:
environmental gradients, boundaries, and buffers. New York, CRC, Lewis Pubishers. pp. 221-235.
Uusi-Kamppa, J., Turtula, E., Hartikainen, H., and Ylaranta, T. 1997. The interactions of buffer zones
and phosphorus runoff. In: Haycock, N., Burt, T., Goulding, K., and Pinay, G. (eds.). Buffer zones:
their processes and potential in water protection. The Proceedings of the International Conference on
Buffer zones, September 1996. Electronic version, Haycock Associated Limited, St. Albans,
Hertfordshire, UK. 326 pp.
Van Vliet, M. and Zwolsman, J. 2008. Impact of summer droughts on the water quality of the Meuse
river. Journal of Hydrology, 353, 1-17.
Vought, L., Dahl, J., Pedersen, C., and Lacoursiere, J. 1994. Nutrient retention in riparian ecotones.
Ambio, 23, 342-348.
72
-------
Ward, A.D., and Trimble, S.W. 2004. Environmental hydrology, second edition. CRC 122 Press LLC,
2000 N.W. Corporate Blvd., Boca Raton, Florida 33431, 475 pp.
Weixelman, D., Zamudio, D., and Zamudio, K. 1996. Central Nevada riparian field guide. R4-ECOL-
96-01. USDA Forest Service, Intermountain Region. 145pp.
Welsch, D. 1991. Riparian forest buffers-function and design for protection and enhancement of water
resources. USDA Forest Service Pub. NA-PR-07-91. 20pp.
Winward, A. H. and Padgett, W.G. 1987. Special considerations when classifying riparian areas. Paper
presented at the symposium, Land Classifications Based on Vegetation: Applications for Resource
Management, Moscow, ID. Nov 17-19.
Winward, A. H. 2000. Monitoring the vegetation resources in riparian areas. Gen. Tech. Rep. RMRS-
GTR-47. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain
Research Station.
Wright, J., Jones, C., and Flecker, A. 2002. An ecosystem engineer, the beaver, increases species
richness at the landscape scale. Oecologia, 132(1), 96-101.
Zimmerman, R. C., Goodlet, J.C., and Comer, G.H. 1967. The influence of vegetation on channel form of
small streams. International Association of Scientific Hydrology 75: 255-275.
73
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