"Lake Hennessey is nestled in the hills on the east side of Napa Valley midway between Napa and Calistoga. The 850-acre man-made reservoir, measuring 2 miles long by 1.5 miles wide, sits at an elevation of 331 feet. The lake was dammed in 1945 to supply water for the city of Napa. It is fed by Sage Creek, Moore Creek, Chiles Creek, and Conn Creek. Sloping hills surround the secluded and quiet reservoir. The pristine mountain lake is also used for fishing, boating, wildlife viewing, picnicking, and is among the best year-round birding areas in the county. The lake is on the Pacific Flyway and is home to hundreds of species of resident and migratory birds. Potential sightings include bald eagles, golden eagles, hawks, osprey, great blue herons, white egrets, woodpeckers, and loons."