Section 319
NDNPDINT SOURCE PROGRAM SOGGESS STORY
Watershed Program Reduces Sedimentation
\A/ t h H I H A reach of the Rio Cebolla in the Jemez Mountains of north-central
0 " • '• ' * ? H New Mexico was documented as impaired because of excessive
sediment. Assessment data prompted the New Mexico Environment Department (NMED) Surface
Water Quality Bureau (SWQB) to add a 9.1-mile segment of the Rio Cebolla to the 1998 Clean
Water Act (CWA) section 303(d) list of impaired waters for sediment. The U.S. Forest Service
(USFS) implemented Respect the Rio (RtR), a program using public outreach, culvert replacement,
road and trail drainage improvements, and fencing to manage movement of livestock and
recreational vehicles to reduce sedimentation. Sediment levels decreased, and NMED removed the
9.1-mile Rio Cebolla segment from the state's 2008 CWA section 303(d) list of impaired waters.
Problem
Rio Cebolla originates in the Santa Fe National
Forest in the Jemez Mountains approximately
12 miles east of Cuba, New Mexico. It is a tributary
to the Guadalupe and Jemez rivers, and most of the
watershed is on USFS land. Surveys in the Jemez
River Basin documented several exceedances of
New Mexico water quality standards for stream
bottom deposits on a 9.1-mile segment from the
confluence of Rio Cebolla with Rio de las Vacas to
Fenton Lake. Because the segment did not sup-
port the designated use of high-quality, cold water
fishery, NMED added it to New Mexico's 1998 CWA
section 303(d) list of impaired waters for sediment.
In 2003 NMED completed a total maximum daily
load (TMDL) for sediment for the Rio Cebolla. The
TMDL identifies runoff from rangeland and roads
(Figure 1) as potential sediment sources. The TMDL
established target levels that are based on relation-
ships between embeddedness (the degree to which
fine sediments fill the spaces between rocks on a
stream bed), fines (sediment particles that are 2 mil-
limeters or smaller), and biological score. Those
relationships show that at the desired biological
score, the target embeddedness (for fully support-
ing a designated use) would be 45 percent, and the
target fines would be 20 percent.
In 2006 NMED revised the sedimentation/siltation
assessment protocol for wadeable streams in New
Mexico's Mountain Ecoregion. The protocol evalu-
ates percent fines and uses a Macroinvertebrate
Figure 1. This August 2003 photo shows erosion
damage from off-road vehicle use near Rio Cebolla.
Stream Condition Index (M-SCI) in comparison to
a reference stream. The combined score of the
biological and physical parameters indicates if the
stream reach is non-supporting or full supporting.
For example, a reach is considered non-supporting if
percent fines are more than 28 percent over the refer-
ence stream and the M-SCI score is less than 56.70.
Project Highlights
USFS staff from the Santa Fe National Forest initiat-
ed the RtR program in 2001, following a 1999 CWA
section 319-funded project that was specific to the
Rio Cebolla. The RtR program was implemented in
three phases: 2001 to 2004 (phase 1), 2005 to 2008
(phase II), and 2008 through the present (phase III).
The program addresses the three primary land use
activities of concern—recreation, grazing and roads.
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Figure 2. New Mexico
Trout volunteers build
fences to prevent
cars from travelling
off-road.
Figure 3. The same
location as shown
in Figures 1 and 2
after fencing and
restoration were
complete.
Dispersed recreation contributes significantly to
degraded water quality, so the program includes a
major education and outreach component aimed at
the recreational users of the national forest area. An
aggressive outreach campaign effectively increased
awareness and educated people on ways to protect
the stream. Program partners further reduced
recreational impacts by installing fences to prevent
vehicles from crossing the stream (Figure 2). The
partners then worked to restore the closed areas
(Figure 3).
Another component of the RtR program was to
improve riparian conditions through better grazing
management. For instance, in the past, grazing per-
mittees would drive the livestock on foot through
the watershed and riparian areas to the winter
pastures. Now, grazing permittees more frequently
transport their livestock to other pastures using
vehicles. Grazing in riparian pastures is limited to
two weeks per year. Additionally, old fences were
replaced as needed, and upland stock tanks were
constructed to relieve concentrated grazing in the
riparian areas.
Project partners also helped reduce impacts from
roads. They replaced two culverts, which helped to
improve floodplain function, reduce bank erosion
and improve fish passage. Partners also improved
road drainage on selected road segments by
installing French drains using permeable material
to facilitate seepage. In one case, partners installed
three French drains to reconnect an adjacent wet
meadow with springs that the road had previously
intercepted. Those actions have considerably
improved the stream conditions, because road
impacts were a significant factor on the Rio Cebolla.
The RtR program will continue and has been funded
to expand into other watersheds, and the USFS will
continue to maintain and monitor the improvements
achieved on the Rio Cebolla.
Results
NMED conducted water quality surveys on Rio
Cebolla in 2005, which show that both percent
fines and mean percent embeddedness decreased
(Table 1). When NMED applied its revised sedimenta-
tion/siltation assessment protocol to the 2005 survey
data, the results indicated that this reach of the Rio
Cebolla was in full support with respect to sedi-
mentation. Therefore, NMED removed the 9.1-mile
segment from the 2008 CWA section 303(d) list of
impaired waters for sediment.
Table 1. Water quality survey results for Rio
Cebolla above Rio de las Vacas
Survey year
1998
2005
Percent fines
28%
23%
Mean embeddedness
53%
25%
Partners and Funding
The Santa Fe National Forest received several
CWA section 319 grants to conduct the program.
Numerous partners helped restore Rio Cebolla,
including New Mexico Trout, Habitat Stamp Program,
New Mexico Game and Fish, Trout Unlimited,
Backcountry Horsemen, individual permittees and
landowners, Jemez Valley and Cuba schools, Boy
and Girl Scouts of America, Student Conservation
Association and Forest Trust Youth Conservation
Corps. The program was patterned after a similar
USFS program in the Pacific Northwest.
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-09-001LL
December 2009
For additional information contact:
Daniel Guevara, Environmental Scientist
New Mexico Environment Department
Surface Water Quality Bureau
505-476-3086 • daniel.guevara@state.nm.us
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