Publication Summary

The objectives of Ecology's lake water quality assessment program are to identify lakes that are exhibiting water quality problems, to assess significant publicly-owned lakes by estimating the trophic status of monitored lakes, and to promote public awareness of lake ecology and protection. In 1991 and 1992, Ecology's lake water quality assessment program consisted of a statewide volunteer lake monitoring program, supplemented with data collected by Ecology staff. This report presents lake monitoring results and discusses informal case-studies on the effectiveness of three citizen-initiated lake protection efforts. Also included in this report are 46 individual lake assessments, which were written for volunteers who participated in the program.

The objectives of Ecology's lake water quality assessment program are to identify lakes that are exhibiting water quality problems, to assess significant publicly-owned lakes by estimating the trophic status of monitored lakes, and to promote public awareness of lake ecology and protection. In 1991 and 1992, Ecology's lake water quality assessment program consisted of a statewide volunteer lake monitoring program, supplemented with data collected by Ecology staff. This report presents lake monitoring results and discusses informal case-studies on the effectiveness of three citizen-initiated lake protection efforts. Also included in this report are 46 individual lake assessments, which were written for volunteers who participated in the program.

In 1992, the lake water quality assessment program also included sampling sediment from ten lakes for potentially toxic compounds. Results of this sediment monitoring component of the project is reported in "Survey of Chemical Contaminants in Ten Washington Lakes" (Serdar et al., in prep).

In 1991 and 1992, volunteers participating in Washington's Citizen Lake Monitoring Project measured Secchi disk transparency and surface water temperature bimonthly for six months (May through October). To supplement volunteer-collected data, Ecology staff met onsite with each of the volunteers to collect water samples and profile data. In 1991, onsite visits were made during May and early June, and water samples were composited from the epilimnion of each lake. In 1992, the scope of the onsite visits was expanded to include two visits (May and August), and composite samples were collected from both the epilimnion and hypolimnion of stratified lakes. Water samples were analyzed for total phosphorus (TP), total nitrogen (TN), and chlorophyll a during both years. Twenty-three of the lakes monitored in 1992 were also sampled for total suspended solids, total nonvolatile suspended solids, and fecal coliform bacteria.

Carlson's Trophic State Index (1977) was used to evaluate volunteer-collected Secchi depth data and Ecology-collected phosphorus and chlorophyll a data. Trophic state estimates were assigned to a total of 50 lakes; 46 of these lakes were monitored by volunteers during one or both years, and the remaining four lakes were sampled by Ecology staff only. Of the 42 lakes assessed from 1991 data, 19 were characterized as oligotrophic or oligo-mesotrophic, 13 were characterized as mesotrophic or meso-eutrophic, and 10 lakes were characterized as eutrophic. Of the 45 lakes assessed from 1992 data, 21 were characterized as oligotrophic or oligo-mesotrophic, 17 were characterized as mesotrophic or meso-eutrophic, and seven were characterized as eutrophic. One lake, Lake Kahlotus, dried up in 1992 and could not be assessed. There were not enough data available to assess water quality trends in individual lakes.

The majority of lakes were assigned the same trophic state for both 1992 and 1991. The availability of additional TP and chlorophyll a data in 1992 improved the assessments in 1992. Six lakes were assigned improved (less eutrophic) trophic states in 1992 than in 1991, primarily because of these additional data.

Citizen-initiated lake protection efforts from three lakes (Lake Martha, Snohomish County; Phillips Lake, Mason County; and Lake Roesiger, Snohomish County) are described here as case studies of the effectiveness of citizen-initiated lake protection efforts. The major conclusion from these case studies is that for citizen-initiated efforts to be successful, citizen groups need individuals who are highly motivated, well organized, and resourceful in getting the help they need to accomplish their goals.

Additional Federal Clean Water Act grant reporting requirements will be addressed in a separate publication, or in the state's 305(b) report.

Link to EIM data for User Study ID AMS002