Executive summary of 1994 East Lake Sammamish Annual Report

The East Lake Sammamish Basin encompasses about 16 square miles of unincorporated King County, on the eastern side of Lake Sammamish. The Sammamish Plateau is the planning area's dominant land feature. It is glaciated drift plain rising from approximately 50 feet at the Lake Sammamish shoreline to about 500 feet above Lake Sammamish. Figures 1 and 2 of the original document identify the water features of the six subbasins, which include more than 40 inventoried wetlands, with nine wetlands rated as unique an outstanding. Several small lakes, particularly Beaver and Pine, and streams, especially Laughing Jacobs and Pine Lake Creeks, are also important aquatic resources for the area. The small, often seasonally dry streams flow in a predominantly western direction from lake and wetland headwaters over the rolling plateau. The streams then flow down the steep, erosive western slope of the basin, though ravines, before discharging to Lake Sammamish.

The basin currently has a mixed development pattern, ranging from low-density residential and pasture uses to high- density and commercial uses. The area is one of the fastest growing in King County with the population rising by 157 percent during the 1980s, and the planning area population is expected to double again by 2010. Approximately 95 percent of the basin is within the urban growth boundary line under the Growth Management Plan.

The basin's surface water resources are in good to fair condition. The quality of the basin's surface waters, the stability of its slopes and stream channels, and the extent to which residents are protected from flooding and environmental degradation, however, will be threatened as the basin urbanizes. Control of these problems requires implementation of the management program recommended in the basin and nonpoint action plan. The plan has three main management goals: (1) to reduce surface water problems that threaten public health and safety; (2) to protect the value of waterbodies for recreation, fish and wildlife habitat, and aesthetic enjoyment; and (3) to reduce the contribution of nonpoint source pollution to these surface water problems.

Executive Summary

The East Lake Sammamish Basin and Nonpoint Action Plan developed by the Issaquah/East Lake Sammamish Watershed Management Committee with King County Surface Water Management (SWM) Division as the lead agency, was adopted by the King County Council on November 8, 1993, and is in the process of being implemented. The Final East Lake Sammamish Basin and Nonpoint Action Plan was printed in December 1994.

The East Lake Sammamish Basin and Nonpoint Action Plan provides a comprehensive surface water management program for the basin. The goal is to maintain current uses of surface waters for recreation, fish, and wildlife habitat, and prevent public health and safety problems. The plan was developed with the philosophy that the land and waters of the basin must be evaluated and managed as a whole integrated system. In order to address the diverse issues, the plan is comprised of a combination of regulatory and programmatic recommendations. These include land-use regulations, capital improvement projects, and educational programs, all coordinated through the Basin Steward Program and evaluated with an array of monitoring techniques.

Of the 59 basinwide recommendations in the plan, 15 programs are in service, 12 are in progress, 4 are being planned, 3 are being revised, and 3 are implemented through Countywide programs. Of the remaining recommendations, 5 were eliminated during adoption by Council, and 17 are inactive. The regulatory programs are in service while the programmatic recommendations are under development.

The Basin Steward Program, an integral part of the plan, is working successfully by providing citizen response and education, and by participating in project implementation and monitoring. The Basin Steward made 27 presentations during 1994, educating over 1,800 people regarding aquatic resources and watershed stewardship. Volunteers are responsible for collecting a large portion of the monitoring data in the basin and their activities included amphibian surveys, kokanee surveys, rainfall and lake water quantity and quality data. The steward helps coordinate these volunteers. A major focus for the year was to have the steward and other SWM Division staff train the Department of Development and Environmental Services (DDES) staff to implement the regulatory portions of the plan and to produce the final plan.

The plan proposed 47 capital improvement projects (CIPs) to control flows and erosion, to reduce water pollution, and to repair damage to aquatic habitat. Two projects were constructed in 1994, and three projects are being designed for construction in 1995.

One of the major concerns in the basin is controlling erosion and sedimentation. The Temporary Erosion and Sediment Control (TESC) Program in King County is focused on the East Lake Sammamish Basin, with monitoring sites measuring sediment and phosphorus levels from a developing area and from an urbanized portion of the basin. In addition, there has been an inspector hired through grant funding to inspect sites for compliance with their TESC plans. The inspector visited 197 sites in 1994, some up to 30 times, and has completed enforcement actions, notices of deficiency, and notices of violations to ensure compliance.