Water: Nonpoint Source Success Stories
New Mexico: Lower Bitter Creek Restoration Project: Sediment Loads Reduced by Implementing BMPs
|Story 1 | Story 2 | State Water Quality Site|
Michael W. Coleman
New Mexico Environment Department
P.O. Box 26110
Santa Fe, NM 87502
|Primary Sources of Pollution:|
|degraded stream channel conditions|
|Primary NPS Pollutants:|
|road drainage improvements/outlets|
|construction of sediment retention basins|
|reduced sediment delivery|
|improved turbidity readings|
Bitter Creek is a perennial-to-intermittent stream that flows into the Red River, a major tributary of the upper Rio Grande system, in northern Taos County, New Mexico. The Bitter Creek subwatershed is immediately northeast of the town of Red River. Nonpoint source pollution, primarily from heavy sediment delivery, was identified as a significant contributor to water quality impairment of the Red River.
An interagency cooperative pollution prevention project was initiated with the Carson National Forest (CNF) Supervisor's Office, the Questa Ranger District (QRD), and the Town of Red River, with participation from local watershed residents. The project was designed to improve degraded stream channel conditions, correct road construction and maintenance practices, remedy illegal refuse disposal, and arrest the rapidly developing headcut impacts. The project also attempted to address the area's altered and mineralized volcanic geology input by mitigating the effects of unchecked erosion from a landslide/debris flow system overlooking the local Forest Service road and the Bitter Creek channel.
Arresting impacts of sediment delivery through BMPs
A number of best management practices (BMPs) were designed to reduce the impacts of turbidity and sediment delivery (with potential for heavy metal loading) in the watershed. A series of road drainage outlets and diversions were constructed to modify and improve drainage along the local forest system road. These outlets reduce the tendency for precipitation or snowmelt runoff to be confined to channelized road segments before accessing degraded slopes via deep headcuts. Highly turbid road and headcut runoff is therefore prevented from delivering sediment directly to Bitter Creek.
In a particularly erodable stream segment known as "the Logjam," a set of energy dissipation and sediment aggradation measures have provided streambank and bed stability. The Town of Red River also constructed a series of in-channel sediment retention basins to slow flow, settle out suspended sediment, and allow channel bottom and floodplain aggradation. This approach aids in the development of a riparian plant community, creating an improved local habitat.
At the suggestion of the local residents, a sediment and runoff retention basin was constructed in the Bitter Creek Debris Flow. The Debris Flow is a surface feature formed by the accumulation of landslide debris running off the Bitter Creek Scar's hydrothermally altered volcanic breccia that forms a high ridge overlooking the region. The favorable performance of the basin minimized the effects of outflow and runout for four large runoff events during 1999-2000, holding back most of the materials that would previously have affected the local road and restricted access into the Bitter Creek channel. This BMP implementation effort represents a temporary fix, and annual maintenance is necessary for this basin to continue to function. Convincing an agency or the local residents to take ownership of the BMP measure remains a target for this 319 project.
This project succeeded in identifying and mitigating a variety of nonpoint source impacts and in demonstrating effective approaches that land management agencies or local residents can adopt and maintain as they seek to preserve their environment and minimize the area's downstream effects. A series of measures were successfully implemented to reduce and control runoff from the roads and slope headcuts. The construction of in-channel revetments is aimed at long-term reduction of sediment loads from the stream system. Overall, the targeted decrease in turbidity of the flow that Bitter Creek delivers to its confluence with the Red River is being realized (see table). Lasting success at Bitter Creek, the Red River, and the Upper Rio Grande will require at least some level of continued monitoring and maintenance.
Bitter Creek Turbidity Sampling Before BMP Installation
|At Red River confluence||9/13/1988||110 NTU|
|At Red River confluence||4/29/1992||125 NTU|
|Upper Bitter Creek||7/24/1992||1.33 NTU||Headwaters|
|Above Two Lakes||8/31/1994||24.7 NTU||Turbidity measured above Two Lakes and debris flow reach|
|Above Red River||8/31/1994||1,000 NTU||Heavy rain event and runoff mobilizing abundant sediment|
|Below gravel pits||4/6/1999||21.7 NTU|
|Below Logjam||4/22/1999||19.5 NTU|
|At Red River culvert||4/22/1999||42 NTU||Turbidity sampled during local gravel sorting/hauling activities|
|Above Red River confluence||5/10/1999||231 NTU||Spring 1999 TMDL|
|Above Red River confluence||5/11/1999||85.2 NTU||Spring 1999 TMDL|
|Above Red River confluence||5/12/1999||40.3 NTU||Spring 1999 TMDL|
|Above Red River confluence||5/13/1999||48.3 NTU||Spring 1999 TMDL|
Project Implementation Begins to Show Effects
|Below Scar Creek||5/21/1999||15.1 NTU||High flow (bankfull conditions thru Town of RR)|
|At Logjam||5/21/1999||16.8 NTU||High flow (bankfull conditions thru Town of RR)|
|At Red River confluence||5/21/1999||112.5 NTU||High flows mobilize sediment from gravel pits (clean upstream)|
|Above Logjam||5/26/1999||12 NTU||Low flow conditions resumed|
|Above gravel pits||5/26/1999||13 NTU|
|Below gravel pits||5/26/1999||24.7 NTU||Gravel operations continue to impact stream flow|
|Above Red River confluence||8/17/1999||15.5 NTU||Summer 1999 TMDL|
|Above Red River confluence||8/18/1999||6.91 NTU||Summer 1999 TMDL|
|Above Red River confluence||10/25/1999||15 NTU||Fall 1999 TMDL|
|Above Red River confluence||10/26/1999||15.3 NTU||Fall 1999 TMDL|
|Above Red River confluence||10/27/1999||8.34 NTU||Fall 1999 TMDL|
|Above Red River confluence||10/27/1999||16 NTU||Fall 1999 TMDL|
|Above Town of RR basins||5/21/2000||88.3 NTU||Flow entering Town of RR basins from upstream.|
|Below Town of RR basins||5/21/2000||8.1 NTU||Settled base flow exiting sediment basins|
Note: RR = Red River; NTU = nephelometric turbidity units
|Story 1 | Story 2 | State Water Quality Site|
Valle Grande Grass Bank Water Quality Improvement Project:
Success Breeds More Success
The Conservation Fund
|Primary Sources of Pollution:|
|Primary NPS Pollutants:|
|establishment of public land grass bank program|
|improved grasslands/ecological diversity|
Grasslands and meadows in northern New Mexico have been experiencing continued decline because of the combined effects of fire suppression and historical grazing. The loss of grass communities has diminished ecological diversity in the regional landscape and has contributed directly to high rates of soil erosion and consequent nonpoint source pollution throughout the region. It has also eroded the viability of northern New Mexico's small-scale Hispanic ranching community, which depends on the use of public lands throughout the region.
Nearly all of the ecological communities that support grazing in northern New Mexico depend on recurrent low-intensity fire to arrest the encroachment of trees and shrubs. It follows that a central challenge in restoring grassland diversity and productivity is to restore fire to its natural role in structuring and renewing the regional landscape. Simply removing cattle from public lands will not restore environmental diversity and health because it will not bring the keystone process of fire back into the landscape.
Rise of the grass bank program
In 1996 The Conservation Fund (TCF), with the assistance of the Forest Service, studied the feasibility of establishing a public land grass bank in northern New Mexico. In 1997 the study led to the formation of a steering committee composed of representatives from the Forest Service, the Cooperative Extension Service, the Northern New Mexico Stockmen's Association, and The Conservation Fund. In August 1997 TCF acquired 240 acres of land on Rowe Mesa, south of the town of Pecos in San Miguel County, renaming it the Valle Grande Ranch. Purchase of the land qualified TCF to become the sole grazing permittee of the adjacent 36,000-acre Valle Grande grazing allotment within the Santa Fe National Forest.
The grass bank program allows participants (selected by the supervisor of the Santa Fe National Forest based on the steering committee's recommendation) to have cattle delivered to the Valle Grande allotment and placed in the care of a full-time cowboy and range rider provided by TCF. By placing their cattle on the grass bank, participating permittees rest their "home" allotments, allowing their pastures, for instance, to grow a crop of grass that will fuel a prescribed fire. Participation in the grass bank usually lasts several growing seasons, allowing desired vegetation to become resilient following restoration treatments.
The first cattle arrived on the Valle Grande Grass Bank in March 1998. By mid-summer, the ranch held 264 cows from four allotments. Gradually, the reputation of the grass bank grew. By January 1999 the steering committee had received applications from seven allotments requesting three times the amount of grazing than was actually available. During the summer of 1999, 346 cows and their calves, belonging to 19 permittees from three allotments, grazed on the Valle Grande Grass Bank.
Land treatment projects: a significant component
In fiscal year 2000, funding from the 319 program helped to support a composite of land treatment projects involving six grazing allotments and five New Mexico watersheds throughout the Santa Fe and Carson National Forests. The unifying purpose is to obtain improved grazing management and ecological restoration that will produce healthy watersheds and reduce nonpoint sources across a wide spectrum of northern New Mexico. Success on these allotments will ensure that permittees on other allotments will want to participate in the Valle Grande Grass Bank program or similar programs at a future date across a broad spectrum of watersheds.
Land treatment projects generally involve burning and thinning to reduce tree and brush densities and to increase effective vegetation ground cover, thus reducing soil erosion and off-site sedimentation and turbidity. Grass bank resting is also necessary to ensure maximum fine fuels prior to burns and to provide rest for establishing seedlings on projects that involve disturbed soil. Road projects are also implemented to improve drainage and appropriate channel crossings, and in some cases might also include closure. Ultimately, 5,800 acres will be burned; 1,475 acres will be thinned; 6 miles of fencing will be constructed; and 5 miles of road will be treated.