PARENT SESSION
Poster Session #21: Riparian and Wetland Restoration.
Tuesday, August 6. Presentation from 5:00 PM to 6:30 PM. Exhibit Hall B & C, TCC

Wetland restoration at the Upper Truckee Marsh, South Lake Tahoe, CA: Implementation and first year's monitoring.

Patterson, Steven^*,1, Wilkinson, Brian², ¹ EDAW, Inc., Sacramento, California² California Tahoe Conservancy, South Lake Tahoe, California

ABSTRACT- Implementation of ecological restoration of a portion of the historic Upper Truckee Marsh by the California Tahoe Conservancy began in the summer of 2001. We report on the project's progress and the results of the first summer's vegetation monitoring. Extensive river and wetland restoration efforts are being undertaken in the Lake Tahoe Basin (California and Nevada, USA) in an attempt to reverse a catastrophic decline in lake clarity. Lake Tahoe's famed clarity is a function of it's extremely oligotrophic state. Urbanization associated with Tahoe's popularity as recreational destination has resulted in greatly increased sediment and nutrient inputs to the lake. Lake clarity has been decreasing by approximately one foot per year for the last three decades. Ecological restoration efforts are a major component of overall efforts to reverse that decline. The California Tahoe Conservancy is undertaking river and wetland restoration at the mouth of the Upper Truckee River, the largest single contributor of flow to Lake Tahoe, supplying approximately 25 percent of runoff entering the lake. During the 1960s, as part of a residential and marina development, material dredged from one part of the marsh was used to fill other portions of the site in anticipation of building. The current project removed approximately five feet of fill from 11 acres to achieve a site elevation approximating the pre-disturbance condition. Following excavation, revegetation was initiated by placement of a 2 inch layer of wetland soil (and its associated plant propagules) across the newly exposed surface, planting of wetland plugs propagated from on-site plant material, and seeding with both site-collected and commercially available seed. Line-intercept transects were used to estimate percent cover and determine first year plant species composition. These data will be compared to species composition of reference sites (less disturbed areas east of the river). Other Conservancy monitoring activities include bird counts and groundwater levels and chemistry.

KEY WORDS: wetland restoration, Lake Tahoe, California, restoration implementation, monitoring