Estimating Predevelopment
Hydrology for Urbanized Areas in
              New Mexico
                  Prepared for
             U.S. Environmental Protection Agency
              Office of Waste water Management
                 Water Permits Division
                  Municipal Branch
                  Prepared by

                  TETRATECH
               One Park Drive, Suite 200 • PO Box 14409
                Research Triangle Park, NC 27709
                 March 2015
           EPA Publication Number 832-R-15-009

-------
(This page is intentionally left blank)

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico                 March 2015
Contents
Contents       	i
1   Introduction	1
2   Predevelopment Hydrological Conditions	2
  2.1   Urban Areas/Clusters	2
  2.2   Elevation and Slope	3
  2.3   Landuse	3
  2.4   Soil	3
  2.5   Meteorological Data	4
  2.6   Pre-development Hydrology Simulation	5
3   Percentile Rainfall Analysis	6
  3.1   Calculating Percentile Rainfall Events	6
  3.2   Rainfall Analysis for New Mexico Urban Areas	7
4   Results and Discussion	10
References     	15
Appendix A    Urbanized Areas/Urban Cluster Boundaries	16
Appendix B    Elevation and Slope	24
Appendix C    Landuse	39
Appendix D    Hydrologic Soil Groups	47
List of Tables
Table 1. Meteorological stations used in the analysis	4
Table 2. 80th, 90th and 95th percentile rainfall events (inches)	8
Table 3. Average annual water balance for each urbanized area	10
List of Figures
Figure 1. Guidance on creating a rainfall frequency spectrum (Hirshman and Kosco 2008)	7
Figure 2. Percentile rainfall analysis	9
Figure 3. Rainfall-runoff response for Farmington	11
    TETRATECH

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico                 March 2015

Figure 4. Rainfall-runoff response for Los Alamos	11
Figure 5. Rainfall-runoff response for Santa Fe	12
Figure 6. Rainfall-runoff response for Albuquerque	12
Figure 7. Rainfall-runoff response for Los Lunas	13
Figure 8. Rainfall-runoff response for Las Cruces	13
Figure 9. Rainfall-runoff response for El Paso	14
    TETRATECH

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico                  March 2015
1   Introduction
Tetra Tech has been contracted by the USEPA to determine representative predevelopment hydrological
conditions in urbanized areas in New Mexico. Managing stormwater to predevelopment hydrological
conditions for newly developed and redeveloped sites is a goal of the existing Middle Rio Grande (MRG)
Watershed Based Municipal Separate Storm Sewer System (MS4) Permit and the proposed Phase IIMS4
General Permit to improve water quality. The MRG Watershed Based MS4 Permit offers discharge
authorization to regulated Phase I and Phase II MS4s within the boundaries of the Bureau of the Census-
designated 2000 and 2010 Albuquerque Urbanized Areas (UAs) and any other MS4s in the watershed
designated by the USEPA as needing an MS4 permit. The proposed Phase II general permit offers
discharge authorization to the rest of the regulated MS4s within the boundaries of the Bureau of the
Census-designated 2000 and 2010 UAs in New Mexico (Farmington, Santa Fe, Los Lunas, Las Cruces
and El Paso). The MRG Watershed Based MS4 permit incorporates a stormwater quality design standard
that manages on-site the 90th percentile storm event discharge volume associated with new development
sites and the 80th percentile storm event discharge volume associated with redevelopment sites. The
Phase II MS4 General Permit is proposing similar stormwater quality design standards (post construction
standards) which uses a percentile storm event approach as a surrogate for mimicking predevelopment
hydrology. In June 2014, USEPA received a petition to designate Los Alamos County, NM (mainly
aimed at Los Alamos and Los Alamos National Laboratory (LANL)) as regulated MS4s. Since it is not
located in a Census UA, the city/county and the LANL federal facility are not currently regulated MS4s
and would have to be designated before a permit for municipal stormwater would be required. This study
includes a similar predevelopment hydrology analysis of the Los Alamos and Whiterock urban clusters.
This study builds on a predevelopment hydrology study in the Middle Rio Grande watershed (Kosco, et.
al., 2014) and uses an updated and more detailed methodology to estimate predevelopment hydrology for
all urbanized areas in New Mexico.
The objectives of this study are as follows,
    1)  Determine representative predevelopment hydrological conditions for urbanized areas in New
       Mexico considering appropriate parameters including rainfall, soil types, topography, land cover
       and evapotranspiration.

    2)  Determine the percentile rainfall relationships for each area of interest.
    3)  Validate if the capture of the 90th percentile storm event is an acceptable standard based upon the
       analyses above.
    TETRA TECH

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico                 March 2015
2  Predevelopment Hydrological Conditions

The Soil and Water Assessment Tool (SWAT) was used to simulate runoff behavior under pre-
development landuse conditions for the Albuquerque, Farmington, Santa Fe, Los Lunas, Las Cruces, and
El Pasco urbanized areas, and the Los Alamos and Whiterock urban clusters. SWAT is a basin-scale,
continuous model that operates on a daily time-step. It is designed to predict the impact of management
on water, sediment and agricultural chemical yields in watersheds and is capable of predicting water
quantity, water quality and sediment yields from large, complex watersheds with variable land uses,
elevations and soils. The model is physically based, computationally efficient and capable of continuous
simulation over long periods (Neitsch et a/., 2011).

SWAT uses a curve number approach to estimate runoff. An initial curve number is assigned to landuses
in the model based upon hydrologic soil group (HSG)  of the underlying soil and slope of the land. Daily
curve number in the model varies based upon antecedent soil moisture; that is, runoff is affected by the
soil moisture before a precipitation event. The curve numbers suggested for different types under different
hydrologic conditions are essentially average curve numbers for average soil moisture conditions (CNn).
Curve numbers may vary from CNi (dry) to CNm (wet). Consideration for antecedent moisture can thus
lower or increase the value of curve number on a given day, with probable impacts on total runoff
volume. It should be noted that this approach utilizes the same basic methodologies as the previously
noted predevelopment hydrology study (Kosco, et. al., 2014) for the Middle Rio Grande watershed with
enhancements to consider antecedent moisture conditions
In a SWAT model, a watershed or study area is divided into several subbasins (urban areas/clusters in this
case), which are then further subdivided into hydrologic response units (HRUs) on the basis of unique
combinations of land use, soil and slope class. An HRU is the smallest physical entity for which all
hydrologic processes are simulated. The hydrologic output at the sub-watershed level is generated by
aggregating the output at the HRU level. HRUs are generated for the model by overlaying spatial datasets
(namely, subbasins, landuse, soil and slope) using the ArcGIS interface of the SWAT model (ArcSWAT).

The following sections discuss the data sources used for the development of the  SWAT model and a brief
discussion of the hydrologic simulation.


2.1  URBAN AREAS/CLUSTERS
A total of 7 urbanized areas (UA)/urban clusters (UC)  were assessed in this analysis.

    •   Farmington UA

    •   Los Alamos and Whiterock UC

    •   Santa Fe UA

    •   Albuquerque UA

    •   Los Lunas UA

    •   Las Cruces UA

    •   El Paso UA

Each of these urbanized areas/urban clusters were modeled as a separate subbasin in the SWAT model.
The pre-development hydrology analysis was conducted for each of these urbanized areas/urban clusters.
Maps of the physical bounds of these urbanized areas/urban clusters are depicted in Appendix A. The El
    TETRATECH

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico                 March 2015
Paso UA includes a significant portion that is in the state of Texas. This area is included in the maps, but
was not included in the analysis.

2.2  ELEVATION AND SLOPE
A 30m resolution digital elevation model (DEM) was used to calculate elevation and slope associated
with the subbasins and HRUs.

Slope is an important factor used in the calculation of curve numbers. The curve numbers suggested by
SCS are appropriate for a 5% slope. As a result, curve numbers in the SWAT model were adjusted for
slope using the equation developed by Williams (1995). Maps of elevation and slope associated with the
urbanized areas/urban clusters are depicted in Appendix B.

2.3  LANDUSE
The use of a landuse dataset that represents pre-development conditions with relative accuracy is
important to address the general objective of this project. The environmental site potential (ESP) dataset
was used for the representation of pre-development landuse conditions in the study area.

The ESP dataset is an abstract concept which represents the vegetation that could be supported at a given
site based on a biophysical environment. The landuse/landcover categories represent the natural plant
communities that would become established at late or climax stages of successional development in the
absence of disturbance. They reflect the current climate and physical environment, as well as the
competitive potential of native plant species. Maps of ESP expressions in the urbanized areas/urban
clusters are depicted in Appendix C.

2.4  SOIL
The USDA's detailed Soil Survey Geographic Database (SSURGO) soil data were generally used in the
SWAT model. The less detailed State Soils Geographic Database (STATSGO), which classifies areas
according to dominant soil components, was used for a small part of the Los Alamos National Laboratory
(LANL) that lacked SSURGO data.

The following properties required for each HRU were extracted from the  soil databases stated above.

    •   Number of horizons
    •   Hydrologic soil group
    •   Maximum rooting depth
    •   Anion exchange capacity
    •   Soil cracking potential

For each soil horizon, the following properties are required and were extracted from the SSURGO  or
STATSGO databases.

    •   Depth of horizon
    •   Bulk density
    •   Available water capacity
    •   Hydraulic conductivity
    •   Percent organic carbon
    •   Percent sand, silt and clay
    •   Percent rock
    •   Albedo

    TETRATECH

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
    •  USLE erosivity factor
    •  Electrical conductivity
Hydrologic soil group (HSG) is of one of the primary properties used in the determination of curve
numbers. A soil may be placed under one of the four groups: A, B, C and D, or three dual classes, A/D,
B/D and C/D. The definitions of these classes are,
A: Sand, loamy sand or sandy loam types of soils. Low runoff potential and high infiltration rates even
   when thoroughly wetted. Consist chiefly of deep, well to excessively drained sands or gravels with a
   high rate of water transmission.

B: Silt loam or loam. Moderate infiltration rates when thoroughly wetted. Consist chiefly or moderately
   deep to deep, moderately well to well drained soils with moderately fine to moderately coarse textures.

C: Soils are sandy clay loam.  Low infiltration rates when thoroughly wetted. Consist chiefly of soils with
   a layer that impedes downward movement of water and soils with moderately fine to fine structure.
D: Soils are clay loam, silty clay loam, sandy clay, silty clay or clay. Group D has the highest runoff
   potential. Low infiltration rates when thoroughly wetted. Consist chiefly of clay soils with a high
   swelling potential, soils with a permanent high water table, soils with a clay pan or clay layer at or near
   the surface and shallow soils over nearly impervious material.

Dual HSGs are assigned to certain wet soils with adequate drainage. The first letter (A, B, C) applies to
the drained condition and the  second (D) applies to the un-drained. Maps of the HSGs of soils in the
urbanized areas/urban clusters are depicted in Appendix D.


2.5  METEOROLOGICAL DATA
SWAT requires daily precipitation, maximum and minimum air temperature, solar radiation, wind speed
and relative humidity for continuous simulation. The minimum required meteorological time series for
SWAT simulations are daily precipitation, and maximum and minimum air temperature. Potential
evapotranspiration (PET) is also required for simulation, but the model estimates it directly using one of
several options. For this model, the Penmann-Monteith energy balance method was adopted for the
estimation of PET using a statistical weather generator for inputs other than temperature and precipitation.

NCDC Summary of the Day meteorological data available from EPA-BASINS were used for the
development of precipitation and temperature forcing files for the model. EPA-BASINS data are filled for
gaps and disaggregated to  an hourly time-step. The EPA-BASINS system does not have data for the
recent years. From 2010 to 2013, precipitation and temperature data were directly downloaded from
NCDC and patched using MetADAPT (an MS Excel based weather data processing tool) to fill data gaps.
One weather station was assigned to each urban area/cluster. The SWAT model was setup for a time-
frame of 34 years from 1/1/1980 to 12/31/2013. Table 1 lists the NCDC stations used forthe
meteorological forcing.
Table 1. Meteorological stations used in the analysis
NCDC ID
290234
293142
295084
295150
298085
298535
412797
NAME
Albuquerque International Airport
Farmington Agricultural Science Center
Los Alamos
Los Lunas 3 SSW
Santa Fe 2
State University (Las Cruces)
El Paso Airport
LAT
35.0356
36.6897
35.8644
34.7675
35.6194
32.2822
31.8111
LONG
-106.622
-108.309
-106.321
-106.761
-105.975
-106.76
-106.376
ELEV (m)
1618.49
1714.5
2262.84
1475.23
2059.23
1182.93
1194.21
    TETRATECH

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico                  March 2015
2.6  PRE-DEVELOPMENT HYDROLOGY SIMULATION
The SWAT model was run from 1/1/1980 to 12/31/2013. Simulation results from the most recent 30-
years (1/1/1984 to 12/31/2013) were used for the pre-development hydrology analysis. The first four
years were used for model spin-up only.
A traditional SWAT modeling exercise consists of calibration and validation for hydrology. Calibration
and validation generally consist of comparing the simulated flow to observed flow until they are in close
agreement with each other. This exercise results in an estimate of model parameter values that represent
the hydrological behavior of the study area. Given the general lack of observed flow data, a soft
calibration strategy was pursued wherein the objective was to have a reasonable representation of the
hydrologic cycle and biomass simulation under pre-development landuse conditions.
    TETRATECH

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico                 March 2015
3   Percentile Rainfall Analysis
Understanding local weather patterns is essential to accurately reflect expected volume, intensity, and
duration of expected storm events with high spatial variability in meteorology. Given the variable but
primarily arid climate of New Mexico where rainfall is generally sparse but ranges due to topographical
variability among other factors, this understanding becomes even more important. A percentile rainfall
analysis utilizes long-term meterological records to evaluate precipitation event distributions in terms of
percentiles. Percentile rainfall analysis is commonly used as the basis for stormwater retention standards.


3.1  CALCULATING PERCENTILE RAINFALL EVENTS
Chapter 4 of the Center for Watershed Protection's (CWP) guidance document for building an effective
post-construction stormwater management program (Hirshman and Kosco 2008) recommends using daily
time step data as an approximation for estimating 24-hour rainfall distributions. Figure 1, taken from the
CWP guidance, describes the process of developing a rainfall frequency  spectrum which is used to
calculate percentile storms for an area. In general, a weather station with at least 30 years of daily rainfall
records is used. Small storms of less than 0.1 inch are edited out and the  entire rainfall record is sorted
from largest to smallest and numbered. A percentile is then assigned based on the total number of rainfall
records (for example, the 10th largest storm out of atotal record of 500 days of recorded rainfall greater
than 0.1 inch would be in the 98th percentile •* (500-10)7500 x 100% = 98%).

Why are small storms not included in calculating the percentile rainfall event?

The rainfall from minor storms may be entirely stored in surface depressions  and eventually lost to
evaporation or infiltration. As a result, no runoff is produced.

Schueler (1987) developed a Simple Method for estimating storm pollutant load export delivered from
urban development sites. From the analysis of National Urban Runoff Program (NURP) data and storm
events recorded at National Airport, Schueler found that the runoff coefficient needed to be corrected to
eliminate the portion of annual rainfall which does not produce any direct runoff. The analysis found that
about 10% of the annual rainfall volume is so slight that no appreciable runoff is produced.
    TETRATECH

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                                              March 2015
   A Rainfall Frequency Spectrum (RFS) Is a tool that stormwater managers should use to analyze and develop local stormwater
   management criteria and to provide the technical foundation for the criteria.

   Over the course of a year, many precipitation events occur within a community. Most events are quite small, but a few can
   create several inches of rainfall. An RFS Illustrates this variation by describing how often, on average, various precipitation
   events (adjusted for snowfall) occur during a normal year.

   The graph below provides an example of a typical rainfall frequency spectrum and shows the percentage of rainfall events
   that are equal to or less than an indicated rainfall depth. As shown, the majority of storm events are relatively small, but there
   is a sharp upward inflection point that occurs at about 1 inch of rainfall (90% rainfall event). The 90% rainfall depth is the
   recommended standard for the Water Quality Volume (see Table 4.7).
     I
     V
     £


     I

     f
                                                                    1
                                            1-year, 24-hour storm = 2.4"
                                            Target for Channel Protection (CP)
90% Rainfall Event = 1"

Recommended Water
Quality Volume I WQv)
               Maximize Runoff Reduction (RR) for All
               Runoff Producing Events Up to the 1 -year,
               24-hour storm
                 10%
                       20%
                             30%
                                   40%    50%    W%

                                      Percentile
                                                       70%
                                                             80%    90%
                                                                         100%
                                   Rainfall Frequency Spectrum
                                   for Mlnneapolls-St. Paul, MN
                                   (1971 -2000) with several
                                   noteworthy rainfall events
                                   Identified (adapted from
                                   MSSC. 2005).
   Guidance on creating an RFS is provided below. If a community is large in area or has considerable variation in elevation or
   aspect, the RFS analysis should be conducted at multiple stations.
   1.  Obtain a long-term rainfall record from an adjacent weather station (daily precipitation is fine, but try to obtain at least 30
      years of daily record). NOAA has several Web sites with long-term rainfall records (see http://www.nesdu.noaa.gov). Local
      airports, universities, water treatment plants, or other facilities might also maintain rainfall records.

   2.  Edit out small rainfall events than are 0.1 inch or less, as well as snowfall events that do not immediately melt.

   3.  Using a spreadsheet or simple statistical package, analyze the rainfall time series and develop a frequency distribution that
      can be used to determine the percentage of rainfall events less than or equal to a given numerical value (e.g., 0.2,0.5,1.0,
      1.5 Inches).
   4.  Construct a curve showing rainfall depth versus frequency, and create a table showing rainfall depth values for 50%, 75%
      90%, 95% and 99% frequencies.

   5.  Use the data to define the Water Quality storm event (90th percentlle annual storm rainfall depth). This Is the rainfall depth
      that should be treated through a combination of Runoff Reduction (Table 4.6) and Water Quality Volume treatment
      (Table 4.7).

   6.  The data can also be used develop criteria for Channel Protection (Table 4.8). The 1-year storm (approximated In some
      areas by the 99% rainfall depth) is a good standard for analyzing downstream channel stability.

   7.  Other regional and national rainfall analysis such as TP-40 (NOAA) or USGS should  be used for rainfall depths or intensity
      greater than 1 year in return frequency (e.g., 2-, S-. 10-, 2S-, SO-, or 100-year design  storm recurrence intervals).
Figure 1. Guidance on creating a rainfall frequency spectrum (Hirshman and Kosco 2008).

3.2   RAINFALL ANALYSIS FOR  NEW MEXICO  URBAN AREAS
A percentile rainfall analysis using the methods discussed above was conducted on continuous fixed 24-
hour interval rainfall data for each of the weather stations discussed in Section 2.5. Daily rainfall events
less than or equal 0.1 inches were ignored. The 90th and 95th percentile event values for each station are
reported in Table 2, and Figure 2 shows the complete percentile rainfall relationship.
     TETRATECH

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
Table 2. 80th, 90th and 95th percentile rainfall events (inches)
NCDC ID
290234
293142
295084
295150
298085
298535
412797
NAME
Albuquerque International Airport
Farmington Agricultural Science
Center
Los Alamos
Los Lunas 3 SSW
Santa Fe 2
State University (Las Cruces)
El Paso Airport
80th percentile
0.48
0.40
0.53
0.48
0.50
0.55
0.54
90th percentile
0.65
0.53
0.69
0.71
0.68
0.78
0.82
95th percentile
0.84
0.70
0.93
0.90
0.87
0.95
1.08
NOTES:
       The previous predevelopment runoff study (Kosco, et. al., 2014) used data from the Albuquerque
       International Airport for the period 1950-2012. Because rainfall data for the other stations studied
       in this report did not extend back to 1950, this report used the most recent 30 year period of
       record (1983-2013) for all stations which resulted in a slightly higher 90th percentile event for
       Albuquerque.
       In terms of implementing the post construction standards in the Albuquerque UA, data should be
       used from the previous predevelopment runoff study (Kosco, et. al., 2014) or estimated through
       site specific pre-development hydrology and associated storm event discharge volume using the
       methodology specified in the 2014 USEPA Technical Report.
    TETRATECH

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                                 March 2015
      NM290234 (Albuquerque)

      NM295150(LosLunas)

      TX412797 (El Paso)
— NM293142 (Farmington)

  - NM298085 (Santa Fe)
- NM295084 (Los Alamos)

- NM298535(LasCruces)
     3.5



      3



   _2.5
   E


  5  2
   c
  "5
  ec.
     1.5
    0.5
      0

        0%     10%    20%     30%    40%    50%    60%    70%    80%    90%    100%

                                        Percentite event
Figure 2. Percentile rainfall analysis
    TETRATECH

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
4   Results and  Discussion
As stated in Section 2.6, a soft calibration approach was adopted to ensure that the hydrologic cycle and
plant biomass were being simulated reasonably by the SWAT model. Table 3 shows the average annual
water balance for each urbanized area over a 30 year period as simulated by the SWAT model.
Table 3. Average annual water balance for each urbanized area
Urbanized
Area/Urban
Cluster
Farmington UA
Los Alamos UC
Santa Fe UA
Albuquerque UA
Los Lunas UA
Las Graces UA
El Paso UA
Potential
Evapotranspiration
(in/yr)
42.95
39.77
42.14
46.31
48.55
53.58
54.72
Precipitation
(in/yr)
8.32
18.70
13.79
9.35
9.75
9.63
9.39
Evapo-
transpiration
(in/yr)
8.02
16.00
12.27
9.10
9.61
9.31
8.85
Surface
Runoff
(in/yr)
0.06
1.74
0.41
0.04
0.02
0.05
0.23
Lateral
Flow
(in/yr)
0.10
0.53
0.28
0.08
0.03
0.13
0.07
Return
Flow
(in/yr)
0.10
0.37
0.80
0.05
0.04
0.13
0.19
The above hydrologic behavior shows a very low surface runoff and high evapotranspiration, which is
expected under pre-development conditions. The average annual simulated biomass (important for
evapotranspiration) was also reasonable with most of the landuses producing more than 1 metric-ton/ha
except for barren landuses.
A rainfall-runoff analysis was then conducted on each of the urbanized areas considered in this study.
Figure 3 through Figure 9 below show the rainfall-runoff response as well as the 90th percentile rainfall
event in each of the 7 urbanized areas/urban clusters. It is evident from the figures that with the exception
of Los Alamos and Santa Fe, runoff generally does not begin until the 90th percentile event. For Los
Alamos and Santa Fe, runoff begins well before the 90th percentile event is reached. It is important to note
that both of these areas have a large percentage of high sloping areas which may be a contributing factor
to higher runoff compare to the other urban areas. The figures also include the 0.6 inch 90th percentile
event for Albuquerque as a comparison.
    TETRATECH
                                                                                          10

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                           March 2015
A Rainfall-Runoff
	 90t
1.000
0.900
0.800
0.700
c
• — n finn
| 0.500
0.400
0.300
0.200
0.100
n nnn i
h percentile


— ^
'elationship Farmington
event







A
A
Att h*.








^ *









A









































0.000
0.500
                              1.000
1.500
  2.000
Rainfall (in)
2.500
3.000
3.500
4.000
Figure 3. Rainfall-runoff response for Farmington
A Rainfall-Runoff
	 90t
1.000
0.900
0.800
0.700
c
ir o.eoo
«•
§ 0.500
0.400
0.300
0.200
0.100
0.000 i
O.C
h percentile







^J
100 0.5
Relationship
event
i
i




00






A
A



A
A
-t .**••
S^
A
A
A A
A
Los Alamos




A
A

A





























S^fe /A ^AA °
1.000 1.500 2.000 2.500 3.000 3.500 4.000
Rainfall (in)
Figure 4. Rainfall-runoff response for Los Alamos
    TETRATECH
                                                                                           11

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                                                            March 2015
A Rainfall-Runoff
	 90t
1.000
0.900
0.800
0.700
c
• — n finn
E
| 0.500
0.400
0.300
0.200
0.100
n nnn i
h percentile







4
,.jAA
Relationship Santa pe
event
1





a
A
*






A
M
tftf










A
A
A A
*t4-'
A &*
i A .. A
S* A
i '
A









































           0.000
            0.500
1.000
1.500
Figure 5. Rainfall-runoff response for Santa Fe
  2.000

Rainfall (in)
2.500
3.000
3.500
4.000
  Rainfall-Runoff Relationship
— Rainfall = 0.6 in
 — 90th percentile event
                                                                            Albuquerque

J..IA/U
0.900
0.800
0.700
0.600
0.500
0.400
0.300
0.200
0.100










1
i



























A
A








A
A






































0.000 0.500 1.000 1.500 2.000 2.500 3.000 3.500 4.000
Rainfall (in)
Figure 6. Rainfall-runoff response for Albuquerque
    TETRATECH
                                                                                             12

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                                              March 2015
A Rainfall-Runoff
	 90t
1.000
0.900
0.800
0.700
c
• — n finn
it
| 0.500
0.400
0.300
0.200
0.100
0.000 A
h percentile










Relationship Los Lunas
event
I







"
i




























A
A
A A i









A
i































           0.000
0.500
1.000
1.500
  2.000
Rainfall (in)
2.500
3.000
3.500
4.000
Figure 7. Rainfall-runoff response for Los Lunas
A Rainfall-Runoff
	 got
1.000
0.900
0.800
0.700
c
r- 0.600
K
| 0.500
0.400
0.300
0.200
0.100
0.000 J
O.C
h percentile









Relationship LasCruces
event







100 0.500






**
l.C

















A
























A A A










i A
&A& A A
OO 1.500 2.000 2.500 3.000 3.500 4.000
Rainfall (in)
Figure 8. Rainfall-runoff response for Las Cruces
    TETRATECH
                                                                                           13

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
A Rainfall-Runoff
	 90t
1.000
0.900
0.800
0.700
c
• — n finn
it
| 0.500
0.400
0.300
0.200
0.100
0.000 t
O.C
h percentile









Relatio
event



A
^^^^^J^H
100 0.500
nshi
ra
m
El Paso






AA







*W A
A
£&£ A
&**> .







A

































1.000 1.500 2.000 2.500 3.000 3.500 4.000
Rainfall (in)
Figure 9. Rainfall-runoff response for El Paso
    TETRATECH
                                                                                         14

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico                  March 2015
References
Hirshman, D. and J. Kosco. 2008. Managing Stormwater in Your Community: A Guide for Building an
       Effective Post-Construction Program. EPA/833/R-08/001. Center for Watershed Protection. U.S.
       Environmental Protection Agency, Washington, DC.
Kosco, J., K. Alvi, and M. Faizullabhoy. 2014. Estimating Predevelopment Hydrology in the Middle Rio
       Grande Watershed, New Mexico. U.S. EPA Office of Wastewater Management. EPA 832-R-14-
       007. http://www.epa.gov/region6/water/npdes/sw/ms4/nfs_albuquerque_report_april2014_v2.pdf
Neitsch, S.L., J.G. Arnold, J.R. Kiniry, and J.R. Williams. 2011. Soil and Water Assessment Tool
       Theoretical Documentation Version 2009. Texas Water Resources Institute Technical Report No.
       406, College Station, TX.
 Schueler, T. 1987. Controlling Urban Runoff: A Practical Manual for Planning and Designing Urban
       BMPs. Metropolitan Washington Council of Governments.

Williams, J.R. 1995. Chapter 25: The Epic Model, p. 909-1000. In V.P. Singh (ed). Computer Models of
       Watershed Hydrology. Water Resources Publications, Highlands Ranch, CO.
    T6TRATECH
                                                                                         15

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico           March 2015

Appendix A    Urbanized Areas/Urban Cluster
                 Boundaries
  TETRATECH
                                                       16

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                              March 2015
          Farmington Agricultural Science Center
                    A/CDC ID: 293142

                                                                      Legend

                                                                        <«>   Weather Station

                                                                       r~*~|  Municipal Boundary
                                                                      t£j[]]  2010 Census Urbanized Area
            Farmington Urbanized Area
                                                            1.5
3 Kilometers
  3
  ] Miles
                                                                                     TETRA TECH
                                                                            Coordinate Sysfem: GCS_North_Amercan_J983
                                                                              Prejection NAD_1983_UTM_ZoneJ 3N
     TETRA TECH
                                                                                                        17

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                   March 2015

                                                                               Santa Fe 2
                                                                           NCDC ID: 298085
                                                                     Legend

                                                                       <8>   Weather Station

                                                                     l~^  I  Municipal Boundary

                                                                           2010 Census Urbanized Area
             Santa Fe Urbanized Area
                                               N     0
1.5
m=
 1
3 Kilometers
 2
                                                                                    TETRA TECH
                                                                           Coordinase System: GCS_North_Amercan_l9
                                                                             Projection NAD_1983_UTM_ZonO 3N
     TETRA TECH
                                                                                                       18

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
                               Los Alamos
                                    Los Alamos
                                National Laboratory

       Legend
       |    | Los Alamos Municipal Boundary
       |    | White Rock Municipal Boundary
            Los Alamos National Laboratory
            2010 Census Urbanized Area
           Los Alamos Urban Cluster
    TETRATECH
                                                                                             19

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
                                                             Albuquerque International Airport
                                                                    NCDC ID: 290234
                                                                    Legend
                                                                         Weather Station
                                                                    I   I  Municipal Boundaries
                                                                         2010 Census Urbanized Area
          Albuquerque Urbanized Area
                                                                         Coordinase Sysfem: GCS_North_Amercan_!9e3
                                                                           Prqection NAD_1983_UTM_ZonO3N
    TETRA TECH
                                                                                                    20

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                                         March 2015
                   Isleta Pueblo
          Los Lunas
       Los Lunas 3 SSW
       NCDC ID: 2951


       Los Chaves
       Be/en

Los Trujillos-
Gabaldon
                                        s/?/o Communities
                                                                   Legend

                                                                    <$>   Weather Station

                                                                   l~*~l  Municipal Boundaries

                                                                        2010 Census Urbanized Area
           Los Lunas Urbanized Area
                                              N     0
                       1.5   3
                            3 Kilometers
                        1.25    2.5
                               3 Miles
                                                                                 TETRA TECH
                                                                        Coordinate System: GCS_North_Amercan_!983
                                                                          Projection NAD_1983_UTM_Zone_13N
    TETRA TECH
                                                                                                   21

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                              March 2015
                                                                       State University (Las Cruces)
                                                                          ' A/CDC ID: 298535
                                                                       Legend
                                                                            Weather Station
                                                                       l~^ I  Municipal Boundary
                                                                            2010 Census Urbanized Area
            Las Cruces Urbanized Area
                                                N     0
                                                            1.5
3 Kilometers
  3
  ] Miles
                                                                                     TETRA TECH
                                                                            Coordinate System: GCS_Nortn_Amercan_l9B3
                                                                              Projection NAD_1983_UTM_ZonO3N
     TETRA TECH
                                                                                                        22

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                         March 2015
                                                                       Legend

                                                                        <«  Weather Station

                                                                       it Municipal Boundary
                                                                            2010 Census Urbanized Area
                                                                     El Paso Airport
                                                                    A/CDC ID: 412797
              El Paso Urbanized Area
0   3.25   6.5

0     2.75     5.5
                                                                                      TETRA TECH
                                                                            Coordinate System: GCS_North_Amercan_!9B3
                                                                      Miles     Projection NAD_1983_UTM_Zone_13N
     TETRA TECH
                                                                                                         23

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico            March 2015
Appendix B     Elevation and Slope
   TETRATECH
                                                             24

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                    March 2015
                                                                               Legend

                                                                                     Farmington

                                                                                     Rivers & Streams

                                                                               Elevation (m)

                                                                               Value
                                                                                     High : 1805.32


                                                                                     Low : 1588 45
           Farmington Urbanized Area:
                     Elevation
                                                N     0
1.25   2.5
      3 Kilometers
   1      2
         : Miles
TETRATECH
                                                                           Coordinate System: CCS North_A.mercan_l9E3
                                                                             Projection NAD_1983_UTM_Zone_13N
     TETRATECH
                                                                                                       25

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
                                                                             Legend

                                                                                  Farmington

                                                                                  Rivers & Streams
                                                                             Slope (%)
           Farmington Urbanized Area
                      Slope
                                                                         Coordinate System- GCS_ri:)rtn_Amer<:an_1W3
                                                                           Prelection NAD 'I9S3 UTW Zone 13N
    TETRATECH
                                                                                                    26

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                  March 2015
                                                                               Legend

                                                                                     Santa Fe

                                                                                     Rivers & Streams

                                                                               Elevation (m)
                                                                               Value
            Santa Fe Urbanized Area:
                      Elevation
                                                           1.6
1.25
    3 Kilometers
       2.5
                         TETRA TECH
                                                                           CoordinaHs Syslem: GCS_North_Amercan_l9B3
                                                                             Prqectlixl NAD_19S3_UTM_Zone_13N
     TETRA TECH
                                                                                                        27

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
                                                                            Legend
                                                                                 Santa Fe
                                                                                 Rivers & Streams
                                                                            Slope (%)
            Santa Fe Urbanized Area
                      Slope
                                                                         Coordinate system GuS_r<3rtn_Arnercan_ly63
                                                                           Prelection NAD 'IW2 UTM Zone 13N
    TETRATECH
                                                                                                    28

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
       Legend
             Los Alamos Municipal Boundary
             White Rock Municipal Boundary
       |     | Los Alamos National Laboratory
             Rivers & Streams
       Elevation (m)
       Value
           Los Alamos Urban Cluster
                    Elevation
    TETRATECH
                                                                                                29

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
                                                               Legend
                                                              |    | Los Alamos Municipal Boundary
                                                              |    | White Rock Municipal Boundary
                                                                    Los Alamos National Laboratory
                                                                    Rivers & Streams
                                                               Slope (%)
                                                                    0-5
                                                                    5-10
                                                                    > 10
           Los Alamos Urban Cluster
                     Slope
    TETRATECH
                                                                                               30

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
         March 2015
                                                                             Legend
                                                                                   Albuquerque
                                                                                   Rivers & Streams
                                                                             Elevation (m)
                                                                             Value
                                                                                   High : 2101.15

                                                                                   Low: 148849
          Albuquerque Urbanized Area
                     Elevation
TETRA TECH
                                                                          Coordinate System- GCS_North_Amercan_l963
                                                                            PrqectKxl NAD_19fl3_UTM_Zone_13N
    TETRA TECH
                                                                                                     31

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
                                                                           Legend
                                                                                 Albuquerque
                                                                                 Rivers & Streams
                                                                           Slope (%)
                                                                                 0-5
                                                                                 5-10
                                                                                 > 10
          Albuquerque Urbanized Area
                      Slope
                                                                        Coordinate System: GCS_NDrtn_ATOrcan_l9B>3
                                                                 Miles      Prelection NAD 1SB3 UTM Zone 13N
    TETRATECH
                                                                                                   32

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                  March 2015
                                                                               Legend
                                                                                    Los Lunas
                                                                                    Rivers & Streams
                                                                               Elevation (m)
                                                                               Value
           Los Lunas Urbanized Area:
                     Elevation
1.25
] Kilometers
   2.5
   3 Miles
                         TETRA TECH
                                                                           Coordinate System: GCS_North_Amercan_l9B3
                                                                             Prqectlon NAD_1963_UTM_ZoneJ3N
     TETRA TECH
                                                                                                       33

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
         March 2015
                                                                              Legend
                                                                                   Los Lunas
                                                                                   Rivers & Streams
                                                                              Slope (%)
                                                                                   0-5
                                                                                   5- 10
           Los Lunas Urbanized Area:
                       Slope
N     0    1.5   3
A    0     1.25    2.5
TETRA TECH
                                                                          Coordinate System: GCS_North_Amercan_I963
                                                                            Projection NAD_1963_UTM_ZoneJ3N
    TETRA TECH
                                                                                                      34

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
                                                                             Legend

                                                                                  Las Cruces
                                                                                  Rivers & Streams
                                                                             Elevation (m)
                                                                             Value
           Las Cruces Urbanized Area
                     Elevation
                                                                         Cowdinase System: GCS_North_Amercan_!983
                                                                   Miles     Prqectuxr NAD_1W3_UTM_2oneJ3N
    TETRATECH
                                                                                                     35

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
           Las Cruces Urbanized Area
                      Slope
                                                                         Coordinate System- GCS_North_Amercan_l9B3
                                                                           PrqectKxl NAD_19S3_UTM_Zone_13N
    TETRA TECH
                                                                                                     36

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                    March 2015
        United States

         Mexico
                                I
                                                                                Legend

                                                                                c£]  El Paso

                                                                               -^— Rivers & Streams

                                                                                Elevation (m)

                                                                                Value
                                                                                — High : 2009.86

                                                                                 •• Low: 1104.1
             El Paso Urbanized Area:
                     Elevation
                                                N     0
3.25   6.5
      1 Kilometers
  2.5     5
         ] Miles
TETRA TECH
                                                                            CotxdinaM? System: GCS_North_Amercan_t9B3
                                                                              Prqection NAD_1963_UTM_ZoneJ3N
     TETRA TECH
                                                                                                        37

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
                                                                    Legend
                                                                         El Paso
                                                                         Rivers & Streams
                                                                    Slope (%)
                                                                         0-5
                                                                         5-10
           El Paso Urbanized Area
                    Slope
    TETRATECH
                                                                                          38

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico             March 2015
Appendix C     Landuse
Tt
   TETMATECH
                                                               39

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
         March 2015
        Legend
        ^j]  Farmington
       -A/— Rivers & Streams
        SWAT Land Cover Categories
           | Open Water
        |    | Barren Land
           | Evergreen Forest
        |    | Mixed Forest
        |    | Shrub/Scrub
        |    | Herbaceous
           Farmington Urbanized Area:
          SWAT Land Cover Categories
TETRATECH
                                                                         Coordinate System: GCS_North_American_1<
                                                                           Protection- NAD_1983_LJTM_Zone_l3N
    TETRATECH
                                                                                                     40

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
       Legend
            Santa Fe
            Rivers & Streams
       SWAT Land Cover Categories
          | Open Water
       [     | Barren Land
          | Evergreen Forest
       |     | Mixed Forest
            Shrub/Scrub
       |     | Herbaceous
           Santa Fe Urbanized Area:
          SWAT Land Cover Categories
    TETRATECH
                                                                                              41

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                              March 2015
                                                                     Legend
                                                                    |    | Los Alamos Municipal Boundary
                                                                          White Rock Municipal Boundary
                                                                          Los Alamos National Laboratory
                                                                          Rivers & Streams
                                                                     SWAT Land Cover Categories
                                                                        | Open Water
                                                                    |    | Barren Land
                                                                    ^^| Deciduous Forest
                                                                        | Evergreen Forest
                                                                    [    | Mixed Forest
                                                                          Shrub/Scrub
                                                                                                    (
            Los Alamos Urban Cluster:
           SWAT Land Cover Categories
0.75
D Kilometers
  1.5
  ] Miles
                     TETRATECH
                                                                            Coordinate System: GCSJJorth_Amencan_1983
                                                                              Projection- NAD_1983_UTM_Zone_13N
     TETRATECH
                                                                                                         42

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
                                                                        Legend
                                                                        ^j]  Albuquerque
                                                                        -/X~- Rivers & Streams
                                                                        SWAT Land Cover Categories
                                                                           | Open Water
                                                                        |     | Barren Land
                                                                           [] Deciduous Forest
                                                                           | Evergreen Forest
                                                                             Mixed Forest
                                                                             Shrub/Scrub
                                                                        |     | Herbaceous
                                                                           "1 Emergent Herbaceous
                                                                             Wetlands
          Albuquerque Urbanized Area:
          SWAT Land Cover Categories
                                                                          Coordinate System: GCS_Nortti_Amenc
                                                                            Projection- NADJ983_UTM_Zone_13N
    TETRATECH
                                                                                                     43

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                                                                  March 2015
                                                                        Legend
                                                                              Los Lunas
                                                                              Rivers & Streams
                                                                        SWAT Land Cover Categories
                                                                           | Open Water
                                                                              Barren Land
                                                                              Mixed Forest
                                                                              Shrub/Scrub
                                                                              Herbaceous
                                                                              Emergent Herbaceous
                                                                              Wetlands
                                                     D    1.5    3
                                                                Kilometers
                                                           1.25     2.5
                                                                   Miles
 Los Lunas Urbanized Area:
SWAT Land Cover Categories
                                                                Coordinate System: GCS_North_Amencan_1983
                                                                  Protection NAD 1983JJTM_Zone 13N
    TETRATECH
                                                                                                      44

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                        March 2015
        Legend
        uH"] Las Cruces
        -N/V— Rivers & Streams
        SWAT Land Cover Categories
           | Open Water
        |     | Barren Land
        |	| Mixed Forest
        |     | Shrub/Scrub
        |     | Herbaceous
             i Emergent Herbaceous
             Wetlands
           Las Cruces Urbanized Area:
          SWAT Land Cover Categories
0   1.75   3.5
0     1.5     3
              Miles
                                                                          Coordinate System: GCS_North_American_1983
                                                                            Projection NAD_1983JJTM_ZoneJ3N
    TETRATECH
                                                                                                      45

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                        March 2015
         United States
          Mexico
                                                                    Legend
                                                                    t£^]  El Paso
                                                                    ~A/^~ Rivers & Streams
                                                                    SWAT Land Cover Categories
                                                                       | Open Water
                                                                    |     | Barren Land
                                                                       | Evergreen Forest
                                                                    |     | Mixed Forest
                                                                    |     | Shrub/Scrub
                                                                          Herbaceous
                                                                          Emergent Herbaceous Wetlands
                                                                                                  _
              El Paso Urbanized Area:
           SWAT Land Cover Categories
0   3.25   6.5
0     2.5     5
             ] Miles
TETRA TECH
                                                                           Coordinate System: GCS_North_Amencan_1983
                                                                             Projection NAD_1983_UTM_ZoneJ3N
     TETRA TECH
                                                                                                        46

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico            March 2015
Appendix D     Hydrologic Soil Groups
   TETRATECH
                                                           47

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
                                                                         Legend

                                                                               Farmington

                                                                               Rivers & Streams

                                                                         Hydrologic Soil Group
          Farmington Urbanized Area
              Hydrologic Soil Group
                                                                        Coordinate System- GCS_Nortn_Amer<;an_t9B3
                                                                          ProjKt!c-v Al&ers Corical Equal Area
    TETRATECH
                                                                                                   48

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                             March 2015
                                                                          Legend

                                                                               Santa Fe

                                                                               Rivers & Streams

                                                                          Hydrologic Soil Group
            Santa Fe Urbanized Area:
              Hydrologic Soil Group
N     0    1.5    3

A    0     125    2.5
TETRATECH
                                                                         Coordinaie System: GCS_North_Amercan_l9E3
                                                                   Miles     Prcjecaofi NAD_1983_UTM_ZoneJ3N
    TETRATECH
                                                                                                    49

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
         March 2015
                                                                             Legend

                                                                                  Albuquerque

                                                                                  Rivers & Streams
                                                                             Hydrologic Soil Group
          Albuquerque Urbanized Area
              Hydrologic Soil Group
TETRATECH
                                                                         Coordinate System: GCS_North_Amercan_l9E3
                                                                           Projection NAD_1983_UTM_ZoneJ3N
    TETRATECH
                                                                                                    50

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
March 2015
                                                              Legend
                                                                   Los Alamos Municipal Boundary
                                                                   White Rock Municipal Boundary
                                                                   Los Alamos National Laboratory
                                                              ->A/~- Rivers & Streams
                                                              Hydrologic Soil Group
                                                              Hi A
                                                                   B
                                                              ^H c
                                                              ^H D
                                                                   Not classified
           Los Alamos Urban Cluster
             Hydrologic Soil Group
    TETRATECH
                                                                                               51

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                       March 2015
                                                                          Legend

                                                                                Los Lunas

                                                                                Rivers & Streams

                                                                          Hydrologic Soil Group
           Los Lunas Urbanized Area:
              Hydrologic Soil Group
0   1.5    3
          3 Kilometers
      1.25    2
TETRA TECH
                                                                  ~      Coordinate System: GCS_North_A™rcan_!983
                                                                  Miles     Prqection NAD_1Se3_UTM_Zone_13N
    TETRA TECH
                                                                                                     52

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
         March 2015
                                                                          Legend

                                                                               Las Cruces

                                                                               Rivers & Streams

                                                                          Hydrologic Soil Group
Las Cruces Urbanized Area:
    Hydrologic Soil Group
                                                    0   1.75   3.5

                                                    0      15      3
TETRA TECH
                                                                         Cowdinaws System: GCS_North_Arrercan_l9B3
                                                                   Miles     Projection NAD_19S3_UTM_Zone_13N
    TETRA TECH
                                                                                                    53

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico
                                March 2015
                                                                        Legend
                                                                             El Paso
                                                                             Rivers & Streams
                                                                        Hydrologic Soil Group
                                                                        •• A
                                                                             B
                                                                        ^H c
                                                                        ^| D
                                                                           fi, Not classified
New Mexico
 Texas
        United States
          Mexico
            El Paso Urbanized Area:
             Hydrologic Soil Group
    TETRATECH
                                                                                              54

-------
Estimating Predevelopment Hydrology in Urbanized Areas of New Mexico                 March 2015
"It
    TETRATECH
                                                                                        55

-------