In 2009, Humboldt Baykeeper initiated an internship program in conjunction with Dr. Alison Purcell O’Dowd, Assistant Professor and Environmental Science Program Coordinator at Humboldt State University. Interns are students enrolled in Applied Ecological Restoration (ENVS 450) who study riparian and instream conditions in Widow White Creek, a tributary of the Lower Mad River in McKinleyville.
Why Widow White Creek?
Widow White Creek has been impacted by urbanization of 25% of the watershed, as well as logging and low-density residential development in the upper watershed. It historically supported coho salmon, steelhead trout, cutthroat trout, three-spine stickleback, and sculpins, and thus is an important target for restoration. Citizen "First Flush" monitoring over several years has found extremely high levels of fecal coliform in the creek, particularly at monitoring sites near residential and commercial areas. The sources of the coliform bacteria are unknown.
Most of the Widow White Creek watershed lies within the unincorporated community of McKinleyville. The watershed has lost 33% of its timber and meadow areas compared to historic conditions.
By 2001, one-quarter of the watershed was classified as “dense urban” by Klein and Anderson. In their analysis on the effects of urbanization on flood frequency estimates for lower Widow White Creek, they found that the 2-year flood flow has increased 229% over pre-development conditions.
As McKinleyville's agricultural lands and forests were converted to residential developments, increased runoff from pavement and rooftops caused higher peak flows during storm events. This increase in stormwater runoff resulted in erosion, bank destabilization, and sedimentation in lower Widow White Creek as the channel expands to accommodate the increased flow, damaging riparian and aquatic habitat conditions.
Stream bank erosion degrades rearing and spawning habitat for salmonids and other aquatic species. Spawning habitat is negatively impacted as spaces within gravels are filled with fine sediment from eroding banks, depriving incubating eggs of oxygenated water while making it physically impossible for emerging alevins to swim out of the gravel and into the water column.
Three study sites were selected along lower Widow White Creek. Site 1 is in the lower reach, where Redwood Community Action Agency has completed a variety of restoration projects, including a 2008 bank stabilization project to reduce erosion and restore fish habitat. Site 2 is between the Widow White Creek RV Park and a gas station on Murray Road near Highway 101. Site 3 is south of McKinleyville High School, between the school athletic field and a residential neighborhood. These sites were chosen to represent different habitat conditions and land use, but also based on accessibility.
With three years of data, it is increasingly clear that the restoration activities undertaken by Redwood Community Action Agency in the lower reach of the creek have had a positive effect on instream conditions, pointing to the need for such restoration work further upstream, where aquatic habitat conditions are poor.
Below are some highlights from the Interns' research over the past three years.
Effects of Urbanization on Widow White Creek in McKinleyville, Ca. Tucker Hoog, Jaclyn Inkster, Neill O’Brien, ENVS 450, Fall 2011.
The objectives of this study were to examine in-stream and riparian conditions of the Widow White Creek to examine the impacts of urbanization on in-stream and riparian conditions. In-stream conditions were sampled using benthic macroinvertebrates, turbidity, and substrate by conducting pebble counts and embeddedness surveys. The riparian conditions evaluated were bank stability and canopy cover.
Results: Site 1 was the furthest down stream and had the best scores in benthic macroinvertebrates (BMI), pebble counts, embeddedness, and bank stability. Site 3 was the furthest upstream and had the worst scores in the same parameters.
Benthic Macroinvertebrates: Site 1 had the best Biotic Index and %EPT, indicating a large proportion of water-quality sensitive taxa. These metrics indicate the best habitat and water quality of the three sample sites. The taxa evenness percentage suggests a good range of different taxa without one group dominating over the rest. The low taxa abundance for this site is due to the low sample size of 66 individuals with four kick samples. Site 3 had the worst scores for Biotic Index, %EPT, and taxa evenness; this sample was dominated by almost 90% amphipods. This is likely due to the substrate being composed entirely of sand, indicating poor habitat quality for invertebrates, which need interstitial spaces between pebbles and gravel.
Assessment of In-stream Fish Habitat and Restoration Progress for Widow White Creek, McKinleyville, CA. Ryan S. Kalinowski and Sarah Yancey, ENVS 450, Fall 2010.
Objective: To evaluate current in-stream conditions in the lower reaches of Widow White Creek, compare 2010 conditions to 2009, and determine the quality of salmonid habitat in the restored site relative to the unrestored sites by measuring turbidity, fish barriers, embeddedness, bank stability, canopy closure, invertebrates, and substrate composition.
Benthic Macroinvertebrates: The primary orders used to evaluate levels of water quality include the orders of Ephemeroptera (Mayflies), Plecoptera (Stoneflies), and Tricoptera (Caddisflies) (“EPT”). These orders are considered pollution intolerant, therefore indicate relatively high levels of water quality when present and low levels of water quality when absent (Michigan Environmental Education Curriculum, Stream Monitoring 2010).
Site 1 contained the most total invertebrates and the most pollution intolerant invertebrates, site 2 contained the second most invertebrates and the second most pollution intolerant invertebrates, and site 3 contained the least invertebrates and the least pollution intolerant invertebrates.
The upper reaches were more impacted than the lower, restored reach. It was noted that the upper reaches where centrally located in McKinleyville, and therefore more closely surrounded by urbanization with impervious surfaces.
Restoring the Pieces of Widow White Creek. Rachael Iverson, Amy Teeters, and Justin Villapando, ENVS 450, Fall 2009.
Objective: For each site, we analyzed a number of factors; riparian width, vegetation, riparian density, bank stability, embeddedness, fish barriers, shading, benthic macroinvertebrates, and bed characterization.
Results: The bioassessment reveals that further downstream the water quality improves and is indicated by a huge leap in ephemeroptera, which is a pollutant sensitive species. Upstream, sites 1 and 2, there is a noticeable increase in amphipoda and oligochaeta, which are very pollutant tolerant species. This indicates a decrease in stream quality further upstream.
REFERENCES for more info on Widow White Creek
Klein, R. D. and J. K. Anderson. 2001. Hydrologic and Hydraulic Analyses for Widow White Creek. Unpublished report prepared for the Natural Resources Services division of Redwood Community Action Agency, Eureka, CA.
Redwood Community Action Agency, Natural Resources Services. Widow White Creek Restoration. http://www.nrsrcaa.org/nrs/projpast/widowwhite.htm
Biotechnical Bank Stabilization and Stream Enhancement Project Widow White Creek, McKinleyville, Humboldt County, California. Initial Study, July 16, 2007. Prepared by Natural Resources Services, Redwood Community Action Agency, Eureka, CA. http://co.humboldt.ca.us/pubworks/ww%20bbs%20initial%20study.pdf