Pearl in peril: Grand Jury report looks at health of Donner Lake
TRUCKEE, Calif – Located within the Town of Truckee, Donner Lake is the go-to spot for residents, vacationers, and tourists looking to sunbathe, swim, fish, and paddleboard amongst its beautiful alpine setting.
“Donner Lake and its basin are home to significant natural and cultural resources,” says Michelle Prestowitz, Project Director Truckee River Watershed Council. She continues by saying, “Many people know it as a recreational destination, but it also supports a diverse array of freshwater and wildlife species and habitat, including rare and endangered plants and animals. It is managed as an important water supply reservoir for northern Nevada and is home to commercial businesses and residential neighborhoods.”
One hundred fifty years of physical and ecological impacts associated with natural resource use, development of major infrastructure, and land development, Donner Lake and the larger Middle Truckee River Watershed have actually been listed as impaired for sediment under the Federal Clean Water Act for many years.
Though challenges with Donner Lake’s water quality have been known since 1978, it wasn’t until 2011 that the Environmental Protection Agency labeled the lake as an impaired body of water, due to the presence of organics such as PCBs, Chlordane, and Arsenic. Additionally, in 2011, the California Department of Fish and Wildlife issued a health advisory regarding elevated levels of mercury in fish tissue.
The steepest hillside (1,500 feet), located on the perimeter of Donner Lake, is made up of the most erosive type of rock responsible for landslides. It is also the focus of a report put together by the Nevada County Grand Jury, titled Pearl in Peril.
“The primary focus of the report was on an area that represents approximately 2%-3% of the Donner Lake watershed. The report seemed to then draw broad conclusions relative to the entirety of the watershed, of which more than 80% is outside the Town boundaries and outside of any jurisdictional control of the Town. A significant amount of the land in the Town boundaries are also outside the Town’s jurisdictional control, such as Caltrans, US Forest Service, California State Parks, the California State Lands Commission properties,” explains Becky Bucar, Assistant Public Works Director, Town of Truckee.
The Town will be developing a formal response to the Grand Jury within the next two months. That response will identify areas where the Town agrees with the Grand Jury’s findings, as well as areas where the Town believes the Grand Jury’s findings may have been incorrect, unrealistic, or based on incomplete information. Regardless of the Town’s response to the report, the Town has been, and continues to be committed to working collaboratively with the previously mentioned partners in the interest of maintaining and improving Donner Lake.
Damaged roads, residential areas, utilities, and stormwater management facilities caused by the Interstate 80 drainage and infrastructure being unable to adequately manage stormwater and spring melt runoff in the Donner Basin area, has endangered Donner Lake, and its surrounding environment. Excessive soil erosion threatens the ecosystem’s resilience.
The Grand Jury received complaints from residents of Donner Lake and the Town of Truckee regarding the runoff from Interstate 80, and the maintenance and repair of a residential road in the path of the runoff. These and related issues create significant risks for the homes and residents living on Donner Pass Road, as well as for other residents of Donner Lake, Truckee, and the ecosystem of Donner Basin, and the Truckee River Watershed.
“As it relates to other areas of the Donner Lake Drainage basin, the Town’s primary areas of responsiblilty regarding erosion and runoff are related to maintenance of Town maintained roads and regulations of construction activities on private property that have the potential of discharging sediment. The Town is currently responsible for 17 miles of roads within the Donner Lake watershed. Those roads are designed to transport runoff along and across roadways in a manner that minimizes erosion. In addition, many of the roadways include features designed to capture and subsequently remove sediment prior to that sediment entering Donner Lake. In addition, the Town performs routine street maintenance including street sweeping and drainage cleaning, which further reduces potential sediment sources from the lake,” explains Bucar.
Proposed solutions include improving the treatment of stormwater flowing from drainage culverts on Interstate 80 to better infiltrate stormwater at its source or distribute the flow of stormwater more evenly across the hillside. It is suggested that there be construction of larger sized culverts crossing West Reed Avenue, along with a regular maintenance schedule and/or installation of an established drainage channel carrying water to a more reliable stormwater infrastructure.
The Town of Truckee, the Truckee River Watershed Council, and DIPS (Donner Lake Interagency Partnership for Stewardship), recognize that the 1,500-foot hillside is an area of concern, and should be first priority.
“DIPS identified a number of areas for continued focus on improvement. There are numerous ongoing efforts by the major land managers around Donner Lake to prevent erosion and runoff. This includes proper maintenance of existing dirt roads and trails, restoration of legacy sites, streambank stabilization, and ongoing stormwater management. DIPS also recommends efforts to identify, prioritize, and complete stormwater retrofits in the Town right-of-way, on private streets. Work is also needed to address stormwater inputs from I-80, such as small-scale BMPS and energy dissipation devices to settling basins or infiltration features,” explains Prestowitz.
Between 1960-1964, Caltrans built Interstate 80 above Donner Lake, using a drainage design and technology that is now outdated. According to Caltrans’ 2020 Highway Design Manual, “The fields of hydrology and the hydraulics of highway drainage are rapidly evolving, and it is the responsibility of the engineer to keep abreast of current design practices.”
The Nevada County Grand Jury recommends that the Town of Truckee take on a leadership role, to partner closely with Nevada County and DIPS to assemble a group of stakeholders dedicated to identifying and carrying out erosive hillside, and an outdated drainage system, causing stormwater runoff that is threatening both residential areas and infrastructure.
Identifying and putting into place an effective and lasting solution to the concerning factors will take an alliance of local and state governments, agencies in the private sector, and organizations working together.
To see the Grand Jury report, visit https://www.nevada.courts.ca.gov/system/files/general/helg-donner-lake.pdf.
Support Local Journalism
Support Local Journalism
Readers around Lake Tahoe, Truckee, and beyond make the Sierra Sun's work possible. Your financial contribution supports our efforts to deliver quality, locally relevant journalism.
Now more than ever, your support is critical to help us keep our community informed about the evolving coronavirus pandemic and the impact it is having locally. Every contribution, however large or small, will make a difference.
Your donation will help us continue to cover COVID-19 and our other vital local news.