Tahoe environmental reports show positive progress, challenges

LAKE TAHOE, Calif./Nev. – The Tahoe Regional Planning Agency (TRPA) released comprehensive reports this week including a greenhouse gas (GHG) emissions inventory for the Tahoe Region and an evaluation of the environmental standards that measure Lake Tahoe’s ecological health. Both show substantial improvements even as new challenges arise, according to the agency.

Highlights from the Greenhouse Gas Inventory Report

The Tahoe Region surpassed the initial target of 15 percent GHG emission reduction by 2020. The 2014 Sustainability Action Plan set additional GHG reduction targets of 49 percent by 2035 and net-zero by 2045.

From 2005 to 2018, overall GHG emissions in Tahoe declined 38.7 percent, however, emissions from 2015 to 2018 increased slightly by 4 percent, mostly from the transportation sector. Over the full inventory period, natural gas became the top source of GHG emissions in the Tahoe Basin, largely due to the heat inefficiency of older homes and buildings. Strategies to reach carbon neutrality in the region also support Lake Tahoe Regional Plan goals for mixed-use, environmentally beneficial redevelopment in town centers. The inventory can be viewed at https://tinyurl.com/46jar4a3.

Highlights from the 2019 Threshold Report

Adopted in the 1980s, environmental threshold carrying capacities (thresholds) are the environmental standards TRPA is required to achieve and maintain through a collaborative, basin-wide framework. The four-year evaluation report released this week found that across all nine threshold categories, nearly 80 percent of the standards evaluated had been achieved or had surpassed their target.

The areas that saw the most notable improvement were in fisheries, wildlife, scenic resources, sensitive land restoration, vegetation, air quality, and noise. The target to restore disturbed or developed land in Tahoe’s most sensitive stream zones is on a path to imminent attainment, according to the report.

“With both states now having climate action goals, the Tahoe Region is doubling down with its own strategies and targets to reach climate resilience and carbon neutrality,” TRPA Executive Director Joanne S. Marchetta said. “It’s encouraging to know that basin-wide collaboration is delivering continuous improvements as we reach for these ambitious goals.”

Scientific peer reviews of past threshold evaluations have helped TRPA identify threshold standards in need of updating to ensure actions remain effective. Earlier this year, the TRPA Governing Board adopted a new threshold category for Transportation and Sustainable Communities—the first new threshold category since 1982. Among the standards in this category, per capita vehicle miles traveled aims to reduce reliance on the automobile, reduce GHG emissions, and promote mobility.

The 2019 Threshold Evaluation has also been converted to an interactive, online dashboard to consistently measure and track progress on all threshold categories: (https://thresholds.laketahoeinfo.org)

Key Threshold and GHG Inventory Facts:

- Climate change initiatives must take priority to continue progress on lake clarity, forest health, and aquatic invasive species control.
- Tahoe yellow cress has been removed from the candidate list of the federal Endangered Species Act as multi-agency partnerships complete more beach protection projects called for in the conservation strategy.
- 1,057 acres of stream environment zone have been restored by Lake Tahoe Environmental Improvement Program (EIP) partners, nearly achieving the target set in 1982.
- 85 percent of stream fish habitat was rated excellent or good, which achieves the goal set in 1982. EIP partners restored 14,680 linear feet of streams between 2016 and 2019.
- Peregrine falcons have made a substantial recovery in the Tahoe Basin. EIP partners have worked with hikers and climbers to discourage nest disturbance, resulting in the highest number of peregrine falcons and active nests in decades.
- 93 percent of the evaluated scenic resources met or exceeded the threshold standard. TRPA adopted scenic design standards in the 1990s.
- Measured reductions in transportation emissions from 2005 to 2018 show the success of regional investment in trails and transit to get people out of their cars. Statewide fuel standards and electric vehicles are contributing factors.

Lake Tahoe Environmental Threshold Categories

Air Quality
Fisheries
Noise
Recreation
Scenic Resources
Soil Conservation
Transportation & Sustainable Communities*
Vegetation Preservation
Water Quality
Wildlife

*New as of 2021