Posted on August 26, 2021
Laguna Lake in San Luis Obispo will soon be dredged during a two-week project starting in mid-September, the city said in a news release Monday.
The project is part of the city’s 2014 Laguna Lake Natural Reserve Conservation Plan to maintain the health of the lake and the recreational opportunities within and around it.
Equipment staging and setup for the project will begin Sept. 1, according to the city. The dredging is scheduled to begin Sept. 16 and last 10 full days, according to Bob Hill, the city’s sustainability and natural resources official.
“This program and project have been decades in the making and will help contribute to a better quality of life for many San Luis Obispo community members,” Hill said. “Ongoing maintenance will help restore water quality over time, make the lake deeper, and allow for more recreational opportunities.
“Ultimately, we’re taking care of an important natural resource in our community for the benefit of both people and wildlife.”
The sediment flowing into Laguna Lake from Prefumo Creek has slowly caused the condition of the lake to deteriorate, according to Hill.
On average, one to three inches of sediment are deposited on the lake bed each year from the lake’s watersheds.
Such sediment impacts have caused toxic blue-green algae blooms and other naturally occurring contaminants to build up, according to the city.
Dredging the lake will deepen the lake, which could then enhance wildlife habitat for threatened steelhead trout and local and migratory birds, as well as improving stormwater management and flood control, according to a 2016 city report on the proposed dredging activities.
Recreational opportunities such as kayaking, canoeing, stand-up paddle boarding and fishing could also see benefits, the report said.
“Laguna Lake is a natural treasure,” Hill told The Tribune. “We’re just really excited to start this project.”
Temporary closures of holes at the disc golf course and some parking space closures may occur during the project, according to the city. But all recreational opportunities — such as hiking, disc golf and the playground and dog park — will remain open for the duration of the project.
In addition to the dredging, a stretch of the lake’s shoreline near the parking lot will be restored, Hill said. This is to prevent further deterioration there and stop asphalt from eroding into the lake, he said.
The project is budgeted to cost $715,000, funded through Measure G-20, according to the city.
That’s a big jump from the $350,000 the dredging project was expected to cost, however.
Hill said this is due to the full scope of the project not being fully worked out at the time of initial budget projections in 2016 and 2020.
Dredging was first done at the lake in the summer of 2020. It cost the city about $500,000 and focused on removing about 2,000 cubic yards of accumulated sediment at the mouth of Prefumo Creek.
The city currently plans to repeat the dredging once every other year “to maintain the lake and improve water quality,” it said in the release.
The project will also establish regular water quality monitoring, according to the release.
