Anne Wynn Ecosystems Investigations Program Geological Survey of Alabama Application of the Strategic Habitat Unit (SHU) Model in North River
51 Strategic Habitat Units (SHUs) and Strategic River Reach Units (SRRUs) were designated to focus conservation activities for managing, recovering, and restoring populations of Alabama’s rare fishes, mussels, snails, & crayfishes. The SHUs and SRRUs include a substantial part of Alabama’s remaining high- quality water courses and reflect the variety of aquatic habitats occupied by these species historically and presently.
North River Location of the North River SHU
Before deciding the best way to manage, restore, and recover mussel populations in the North River Watershed, a comprehensive assessment of existing environmental conditions needed to be conducted. GSA performed fish biotic integrity assessments, mussel surveys, and rapid habitat assessments throughout the watershed. They also developed a land cover/ land change dataset. Previous water quality and biological monitoring studies were also documented and summarized in the assessment. The data came from various agencies including the USGS, GSA, City of Tuscaloosa, and ADEM. To access this assessment, visit:
The potential nonpoint source index (PNPI) method was utilized to identify nonpoint pollution sources on the broad landscape scale of the entire North River Watershed. GIS grids of soil impermeability, distance to water, slope, and land cover were established in ArcMap and the raster calculator was applied to the PNPI equation (5 * LCI + 3 * DI + 2 * ROI) to produce the PNPI map. SoilsDistance to water sources Slope Land Cover
Large PNPI values are red on the map, and represent areas having a high probability of contributing nonpoint source pollution. High risk areas included row crop fields/barren land/clear cuts/built up land with impermeable soils on sloped terrain in close proximity to a stream. These areas have the best chance of producing rain runoff carrying sediment, pesticides, E. coli bacteria, and heavy metals to a nearby water source. This map can help prioritize locations for stream habitat and road-stream crossing assessments.
The watershed assessment was not only important for SHU restoration efforts, but was critical for the development of the North River Watershed Management Plan. The North River has been listed on Alabama’s 303(d) list of impaired waters since 1998 for siltation and nutrients. The North River Watershed Management Plan received 319 funding from ADEM in 2010.
Clear Creek subwatershed North River Watershed The watershed assessment findings suggested that the most robust assemblage of mussel species in the North River Watershed was in Clear Creek. Rapid habitat assessments observed high levels of sediment deposition in Clear Creek and its tributaries.
Clear Creek watershed To quantify the current sediment load in Clear Creek, GSA installed two OTT Orpheus Mini Data Loggers. These water gauges began recording water level in Fall 2010.
Suspended sediment grab samples are being collected at the gauging stations. Instantaneous measurements of specific conductance, pH, temperature, dissolved oxygen, & turbidity are also recorded. A standard Price AA or pygmy flow meter is used to record flow measurements at cross-sectional monuments at the gauging stations.
Clear Creek during low flow Clear Creek during a flood event Water quality data has been gathered during dry periods of low base flow, winter flooding, and isolated summer storm events.
The gauge readings, water quality data, and flow measurements are being used to calculate sediment loading rates in the Clear Creek Watershed.
Once the water gauges had been installed and baseline water quality data had been obtained, habitat threat and road-stream crossing assessments began. These assessments helped to determine locations for restorative best management practices
Rosgen Stream Classification Very helpful field manuals PANAMA CITY Fisheries Resource Office HABITAT EVALUATION Field Survey Procedures June 2006 Stream habitat and road-stream crossings were evaluated using methods developed by the USFWS (Chris Metcalf), Science Applications International Corporation (Michael Rainer) and Troy State University (Patrick Witmer and Paul Stewart). Chris Metcalf provided orientation and field training to learn the techniques. Dan Everson w / USFWS also helped our team become more familiar with identifying stable and unstable channel morphology using the Rosgen Stream Classification System.
11 variables = Habitat Threat Severity Index score 1. Water odors 2. Channel stability 3. Channel alteration 4. Shoring structures 5. Fish passage barriers 6. Riparian buffer width 7. Local non-point pollution 8. Floodplain access 9. Bank erosion 10. Pipe discharges 11. Bank Erosion Hazard Index (BEHI)
It takes at least 3 people to perform instream measurements during the Stream Habitat Threat Assessment Taking bank measurements in the North River Watershed
Location of stream habitat threat assessment sites on Clear & Deadwater Creeks
ROAD-STREAM CROSSING SEDIMENTATION RISK INDEX A poorly maintained road-stream crossing is a potential source of sedimentation to a stream. The Sedimentation Risk Index (SRI) was used to evaluate road-stream crossings in the North River Watershed.
12 SRI metrics This survey can be performed by a single person, but two people make it go much faster
SRI conditions in the North River Watershed 62 unpaved and 69 paved sites were assessed. Out of 131 sites, 42 (32%) were at high risk of contributing a lot of sediment to the adjacent stream. 31 (73%) of the high risk sites were unpaved.
What does high risk look like?
Unstable channel morphology No riparian vegetation, incised channel w/ high banks, and no natural meandering indicate an altered stream channel downstream of the crossing. Incised channel w/ high banks, and excessive erosion downstream of the crossing.
Bare soil / bedrock ditches AND steep road approaches
Road crossing fill erosion
Blocked culverts
BMP installed by Overhead Bridge on Deadwater Creek Road-stream crossing and habitat threat assessment data has helped establish BMP locations in the North River. Water quality data will continue to be collected until 2015 to determine if BMPs are helping reduce the watershed’s sediment load.
Broadening the SHU partnership The work done in the North River needs to be performed in other SHUs now. Partners are needed to help with SHU watershed assessments. Assessment data will be hosted on a forthcoming SHU website, which is being developed by the USFWS. The website will give the public access to the SHU database in the form of a statewide interactive map. Stream Habitat Threats and Road – Stream Crossing Assessment sites will be uploaded to the interactive map. This way Clean Water Partners (this could be you!) and other stakeholders will be able to see the current conditions in each SHU and where restoration projects are needed.
Questions? Anne Wynn Ecosystems Investigation Program Geological Survey of Alabama Jennifer Pritchett United States Fish and Wildlife Service Daphne Field Office Contact Us
Acknowledgements