Heart Lake Monitoring Project 2016 Final Report

Heart Lake is located about 2 miles (3.2 km) south of Anacortes off of Heart Lake Road. There are six inlet streams that flow into southeastern side this 61.4 acre lake (0.248 km2). Heart Lake is separated into two basins and has a total shoreline length of 1.64 miles (2.645 km). The western basin is slightly larger and deeper that the eastern basin, but the maximum depth and average depth of the lake is only 5.8 and 2.7 meters, respectively. Heart Lake is part of the Anacortes Community Forest Lands and is a popular recreational destination. Activities on the lake include fishing for the biannually stocked Rainbow trout (Oncorhynchus mykiss) as well as swimming, boating, birding, and picnicking (Washington Department of Fish & Wildlife, 2017). The watershed surrounding the lake contains an extensive recreation trail network that allows dog, horse, pedestrian, and mountain bike traffic (City of Anacortes 2012). There is an active granite quarry just outside of the watershed boundary on the western end of the lake. Heart Lake contains dense patches of submerged and floating aquatic plants (macrophytes). In the recent years, a hybrid between the non-native Eurasian water milfoil (Myriophyllum spicatum) and the native northern water milfoil (Myriophyllum sibiricum) has begun to dominate the shallow lake (Herrera Environmental Consultants, 2014), making recreational access to the lake difficult. In addition to the thick mats of the noxious aquatic plant, dense blue- green algal blooms have become a regular occurrence, resulting in additional hazards to local residents.