Next week, visitors to downtown Olympia and the Capitol Campus will get a rare look at Capitol Lake's lakebed as the Department of Enterprise Services (DES) lowers the water levels to gather data related to the planned Deschutes Estuary.
From July 24, DES will open the water gate on the 5th Avenue Dam for four days, allowing water to flow from the lake into Budd Inlet. As water levels drop, parts of the lakebed will become visible.
The objective of the exposure is to study underwater features such as the dam structure, fish gate, and sediment deposits. The locations of outfall pipes used for stormwater dispersal will also be verified.
DES will also use a drone to capture images of the lakebed. This will help document the conditions and topography, aiding in the design of the restored estuary.
Once the data is collected, DES will close the water gate, allowing the lake to refill naturally. The process will take a few days, with the lake expected to return to normal by August 5.
The collected data will inform the next stage of the restoration design, refining technical requirements.
Aside from studying the underwater features, the lakebed exposure is a unique opportunity for visitors to observe how sediment has built up over time. However, the public should not walk on the exposed sediment due to safety risks and to prevent the spread of invasive species.
Capitol Lake has been closed to the public for recreational use since 2009 due to the presence of the New Zealand mud snail, an invasive species. Increased salt and fresh water mixing in the restored estuary will help control this infestation. In the meantime, crews will decontaminate their equipment to avoid spreading the species.
DES is working on restoring Capitol Lake to its historical estuary state to improve water quality, wildlife habitats, and community use.
The Deschutes Estuary Restoration Project, one of the largest urban estuary restorations in the country, aims to restore 260 acres to a native estuary habitat.
DES will replace the 5th Avenue Dam with a new bridge that includes vehicle, bicycle, and pedestrian lanes.
To stay updated on the project and future public involvement opportunities, subscribe to the project newsletter through the DES sign-up webpage.
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DanaMadsen
It has been fascinating to watch the State Government "study" Capitol Lake as they turn it back into a mud flat. The folks who initially built the dam and created the lake in the first place have not spent one penny or lifted a finger to do any maintenance to stop the natural process of siltation turn the lake into a weed choked swamp. Now that it is a mess, the solution seems to be to reverse the process and rip out the dam and let the lake become a tidal mud flat. What geniuses.
Tuesday, July 23 Report this
Treacy2
Why aren't people asking how future sediment flow will only serve to cover up the Deep Water Port's environmental issues? Until Budd Inlet is cleaned up and an Endowment for regular dredging is established, this is a national scale boon dogle of epic proportion. Can't we just build a highway to nowhere and get everybody paid?
Wednesday, July 24 Report this