Nonpoint Source Projects
2018 State of the Environment Report (WQ)

Success Story: Main Creek

Main Creek is one of several tributaries to Deer Creek Reservoir, an important drinking-water source to Salt Lake City and the Wasatch Front. Deer Creek Reservoir has experienced low dissolved oxygen due to elevated water temperatures and excess cyanobacteria growth as a result of nutrient loading. Main Creek also has high levels of phosphorus and E. coli as well as elevated water temperatures.

In March 2007, the Wasatch Conservation District, along with local stakeholders, met to address resource concerns in the Wallsburg Watershed. Using the Coordinated Resource Management (CRM) process, stakeholders, landowners, and agency personnel evaluated local resources and the potential for actions to protect and restore the watershed. Participants listed water conservation and water quality as the top two resource concerns. Stream-bank restoration was identified in the Wallsburg CRMP as an effective way to lower water temperature and reduce E. coli and total phosphorus (TP) loading to Main Creek and Deer Creek Reservoir. Stream banks were characterized as highly erodible due to lack of riparian vegetation and access by livestock. The shortage of native woody vegetation along the river also allowed for higher in-stream temperature due to a lack of shading.

Streambank restoration projects began on Main Creek in September 2013. Since then, various agencies have spent over $1.6 million to implement projects throughout the watershed, with another $730,000 scheduled for 2019. Currently, over 7.5 miles of stream have been treated and nearly 50,000 feet of fence has been installed to better control grazing within the watershed.

As a result of project implementation, notable improvements have been observed with the Main Creek Watershed. These improvements include significant loading reductions of E.coli and nutrients. The amount of fine sediments in the creek has decreased, and the vegetative cover has increased. The channel has also narrowed and pool depth has increased, leading to decreased water temperatures, and a vast improvement in the biological composition of the restored sections.

Success Story: North Fork Virgin River

The Upper North Fork Virgin River was first included on the Utah 303(d) list of impaired waterbodies in 2010 for failing to meet the E. coli standard for frequent primary contact recreation. The lower watershed was listed in 2012. E. coli is an indicator of fecal contamination in a waterbody.

On any given day in the summer, thousands of people recreate in and along the popular Zion Narrows trail, which is carved by the flow of the North Fork Virgin River. As a result, the potential threat to human health is high, so studying this area, characterizing where and when the problem occurs, and identifying potential solutions were a priority for DWQ staff. E. coli data were collected at multiple sampling sites throughout the watershed on a monthly basis throughout the recreation season of May through October from 2010-2017. Exceedances of the standard were primarily driven by return flows from flood-irrigated pastures grazed by cattle and wildlife.

Various agencies and landowners began working to improve water quality through the implementation of Best Management Practices (BMPs).

• DWQ awarded a nonpoint source grant to the Kanab BLM field office to install a vault toilet at the Chamberlain Ranch trailhead where hikers begin the popular 16-mile Zion Narrows hike. An outhouse at the location was perched over an irrigation canal on the North Fork Virgin River and contributed to high  colilevels in the river. The outhouse was removed in 2015 and replaced with a pit toilet at the trailhead. Since the toilet was installed, there has been a decrease in human waste scattered around the trailhead and overall conditions at the trailhead have greatly improved.
• A prescribed grazing management plan was implemented during the 2015 grazing season on 45 acres of private lands to address coli loading from flood-irrigated pastures in the upper watershed. The grazing management plan had the added benefit of improving riparian areas by increasing streamside vegetation. The increase in riparian vegetation slows overland flow and reduces the pathogens entering the river from the pastures during irrigation and precipitation events.
• Historically, the landowners would divert the maximum amount of water that their system would hold to flood their fields. This excess water increased the potential for bacteria-laden irrigation return flows to enter the river. Irrigators throughout the watershed have been encouraged to install measurement devices, and some already have in several locations.

The collaborative effort between the DWQ, Zion National Park, and the Bureau of Land Management (BLM), the North Fork Virgin River watershed has resulted in intensive monitoring for E. coli during the recreational season. Monitoring data show that elimination of grazing, management of human waste, and improved irrigation-water management has improved the water quality. Since the implementation of these BMPs, there have been no exceedances in E.coli water-quality standards. If DWQ continues to observe no exceedances, the North Fork of the Virgin River may be delisted for E.coli as early as 2020.

Partners and Funding

Stakeholder participation was achieved through multiple meetings and site visits over the past few years. Partners included local landowners, the Bureau of Land Management, Zion National Park, the Utah Division of Water Quality, the Utah Department of Agriculture and Food, the Utah Association of Conservation Districts, and the Utah Division of Water Rights.

Approximately $30,000 has been spent on improvements in the watershed, with funding coming from state, federal, and private sources. The most effective component —the elimination of grazing — was accomplished through landowner education and proper management plans. This story highlights how proper land-use management can improve water-quality without the installation of expensive BMPs.