NONPOINT SOIREE SICCESS STOIY
Agricultural Best Management Practices Improve Aquatic Life in the
Blackwater River
WaterbodieS Improved High sediment loadings led to violations of the general
standard for aquatic life use in Virginia s Blackwater
River. As a result, the Virginia Department of Environmental Quality (DEQ) added two
segments of the Lower Blackwater River to the 2008 Clean Water Act (CWA) section
303(d) list of impaired waters. Landowners installed agricultural best management
practices (BMPs); these decreased edge-of-field sediment loading and helped improve
water quality. Because of this improvement, DEQ removed two segments of the
Blackwater River from Virginia's 2014 list of impaired waters for biological impairment.
Problem
The Blackwater River watershed is in Franklin County,
Virginia, in the Roanoke River Basin (USGS Hydrologic
Unit Code 03010101). The watershed lies north of
Rocky Mount, Virginia, approximately 15 miles south
of Roanoke, Virginia. The Blackwater River flows
southeastward and empties into Smith Mountain Lake
(Figure 1). The Upper Blackwater River watershed
(70,303 acres) is 69% forest, 18% pasture and hay-
land, 7% cropland and less than 1% urban. The Lower
Blackwater River watershed (20,504 acres) is 58%
forest, 33% agricultural, 8% urban and 2% water.
Biological sampling conducted at monitoring sta-
tion 4ABWR029.51 in 2004 showed Virginia Stream
Condition Index (VSCI) scores of 60.7 in the spring
and 50.1 in the fall. The VSCI score is a macroinver-
tebrate and fish community index, a composite mea-
sure of the number and types of pollution-sensitive
aquatic insects inhabiting a waterbody. A VSCI rating
score of 60 or above indicates that a waterbody sup-
ports its biological integrity and meets its aquatic life
designated use.
Because 2004 data showed that the Blackwater River
failed to support biological integrity year-round, DEQ
added two segmentsBlackwater River assess-
ment units VAW-L08R _ BWR01AOO (3.02 miles long)
and VAW-L08R _ BWR01B06 (2.97 miles long)to
Virginia's 2008 CWA section 303(d) list for violating
the general standard (benthic impairments). Water
quality data analyses and field observations indicated
that the primary cause of the benthic impairment in
& Biological Monitoring Station Upper Blackwater River
/\/ US Highway £J> Lower Blackwater River
DelistedWaters-5.99 Miles £3 «h Order Hydrologic Unit
va_2014_aus_riverine 0 O.S 1 1 3 4 Miles
Figure 1. The Blackwater River is in southwest Virginia.
these segments was excessive sedimentation. The
subwatershed area of the listed segments consists
of 7,707 acres and is in the upstream reach of the
Lower Blackwater River watershed.
DEQ developed total maximum daily loads (TMDLs)
for Upper Blackwater River, Middle Blackwater, North
Fork Blackwater and South Fork Blackwater River (for
bacteria in 2001 and for sediment in 2004). TMDLs
for Lower Blackwater River and Maggodee Creek
were developed for bacteria in 2001. The Virginia
Department of Conservation and Recreation (OCR)
developed TMDL implementation plans for the Upper
Blackwater River in 2001 and for the Lower Blackwater
River, Maggodee Creek and Gills Creek in 2006.
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Figure 2. BMPs installed in the Blackwater River watershed
include alternative livestock watering systems (left), and small
grain cover crops (right). Photos courtesy of Blue Ridge Soil and
Water Conservation District.
Project Highlights
A number of agricultural BMPs were installed
from 2002 to 2012 to reduce sediment loads in the
subwatershed area containing the impaired segments.
These BMPs include 29,323 linear feet (5.6 miles) of
livestock exclusion fencing, 258 acres of small grain
cover crop, 37 acres of harvestable cover crop and
38 acres of legume cover crop (Figure 2). Also, various
BMPs were installed in the Upper Blackwater River
watershed, which affected downstream sediment
loads and helped improve water quality. These BMPs
include 42,660 linear feet (8.2 miles) of livestock exclu-
sion fencing, 2,211 acres of small grain cover crop,
344 acres of harvestable cover crop and 96 acres of
legume cover crop. Also, four animal waste storage
facilities were installed in the watersheds.
Results
Water quality in the Blackwater River has improved
due to the installation of agricultural BMPs. The
spring 2012 VSCI score fell slightly below the non-
impaired threshold (field personnel noted a high flow
event two weeks prior to sampling that might have
negatively affected the score); however, the remain-
ing spring and fall scores all remained well above the
threshold value (Figure 3).
The increased VSCI scores reflect an improvement in
biological condition which fully supports the aquatic
life designated uses of the stream. Because of these
improvements, the two previously impaired seg-
ments of the Blackwater River were removed from
the state's impaired waters list in 2014 (as reflected
in the 2014 Water Quality Assessment 305(b)/303(d)
Integrated Report).
100.0
Virginia Stream Condition Index (VSCI)
20.0
0.0
Spring Fall
2004 2004
Spring Fall Spring Fall
2011 2011 2012 2012
Figure 3. Biological assessment VSCI scores in the Lower
Blackwater River (river mile 29.51) improved after BMP
implementation. A score of 60 and above is considered to
be meeting the aquatic life designated use.
Partners and Funding
The improved water quality in the Blackwater River
has largely been the result of partnerships between
Blue Ridge Soil and Water Conservation District
(BRSWCD) and several federal and state agencies,
including OCR, DEQ, and the U.S. Department
of Agriculture's (USDA's) Natural Resources
Conservation Service.
TMDL implementation, including cost-share funding,
outreach activities and technical assistance to imple-
ment agricultural BMPs, was locally administered
by BRSWCD. Outreach efforts included conducting
watershed tours and meetings, making contact with
individuals, and presenting BMP material to landown-
ers and community organizations in the impaired
watersheds.
OCR administered six CWA section 319(h) awards
that collectively provided $329,056 in agricultural
BMP and residential septic cost-share and technical-
assistance funds. OCR also provided $205,127
in state agricultural cost-share funds (including
the state portion of the Conservation Reserve
Enhancement Program [CREP] funding). The USDA
provided approximately $9,783 through CREP.
Landowners and participants provided an estimated
$230,678 of cost-share funds for their portion of
installed practices.
yss
Ill
o
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-16-001B
January 2016
For additional information contact:
Nicole Sandberg, Virginia Department of Environmental Quality
nicole.sandberg@deq.virginia.gov
Mary Dail, DEQ Roanoke Regional Office
Mary.Dail@deq.virginai.gov
Michael Tabor, Blue Ridge Soil and Water Conservation District
mtabor@brswcd.org
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