The end of Puget Sound – or – is it the beginning? No matter. On one side of the road is Capitol Lake and on the other is Puget Sound. No need to go in either the road or the water. During my visits there, I saw great blue herons, two kinds of jellyfish, schools of small fish, and at one point, five harbor seals at the same time.
This is an easy micro designed to bring you to a great view of the Capitol building as well as the end of Puget Sound.
Capitol Lake is actually a 260-acre reservoir. It was created in 1951 when the state constructed an earthen dam, 80-foot concrete spillway and bridge along 5th Avenue in Olympia. The dam blocked the tidal flow of Budd Inlet and changed the mudflats of the Deschutes River estuary into a lake. You can see the fresh water flowing out of the lake at low tide.
The idea of creating a lake came from the 1911 Capitol Campus design plan. The lake was meant to serve as a reflecting pool for the Legislative Building and to enhance the scenic views of the Olympic Mountains and Puget Sound from the Capitol Campus and the hillsides surrounding the city. Deschutes Parkway, which runs along the western shore of the lake, was constructed at the same time as the dam. The state Department of General Administration manages the parkway and the lake.
Sediment transported by the Deschutes River and Percival Creek is slowly filling in the lake. Within the next few years, it is unlikely that the sediment will change the appearance of the north basin of the lake, adjacent to Heritage Park, but islands may appear in the middle basin, near Marathon Park, over the next 10 years. Vegetation will grow on these islands and the lake will gradually have less open water.
The lake is closed to swimming due to high levels of fecal coliform bacteria and phosphorus. These promote the growth of algae and weeds, which in turn rob the water of oxygen as they decay. This causes fish and other aquatic life to die and also reduces water clarity. In addition, there is a massive invasion of milfoil, which will accelerate the process of the lake turning into wetlands.
Water quality is another key lake management issue. The lake is listed on the state Department of Ecology’s list of impaired water bodies for fecal coliform bacteria and phosphorus. In aquatic environments, fecal coliform bacteria pose a potential health risk to individuals exposed to this water. This is one reason why the lake is closed to swimming. A high level of phosphorus promotes the growth of algae and weeds, which rob water of oxygen as they decay.
The Capitol Lake Adaptive Management Plan (CLAMP) Steering Committee was formed in 1997 to weigh alternatives for managing the lake and surrounding property. One option would be to remove the dam and reestablish a saltwater estuary. The overall goals are to improve water quality, fish and wildlife habitat, and public recreational opportunities, while managing flood control, sediment deposits and adjacent infrastructure, such as Deschutes Parkway. Also included are rehabilitation of the fish ladder, relocation of Percival Cove fish-rearing operations, and elimination of noxious weed infestations throughout the lake.