Laguna Lake dredging slowly moves closer to reality

A few ravens stand in shallow Laguna Lake in San Luis Obispo on Thursday. The San Luis Obispo City Council’s goal is to have a dredging and sediment management project for the lake selected and ready to move forward by June 2017.
A few ravens stand in shallow Laguna Lake in San Luis Obispo on Thursday. The San Luis Obispo City Council’s goal is to have a dredging and sediment management project for the lake selected and ready to move forward by June 2017. dmiddlecamp@thetribunenews.com

Laguna Lake typically serves as a home for birds and boaters, providing a peaceful oasis to residents and park-goers in western San Luis Obispo. But four years of drought left the boat ramp sitting in dried mud, killed hundreds of fish and prompted waterbirds to go elsewhere.

Thanks to recent storms, however, the lake now contains more water than it has in several months — though that water is brown, muddy and only ankle-deep.

As the water level gradually rises, the process to dig out decades of silt build-up that is slowly filling in the lakebed is also moving slowly ahead.

The city plans to spend up to $445,000 for a consultant to survey the lake, design three different dredging options and one excavation project for city leaders to consider, prepare cost estimates and provide a report of possible types of financing. Dredging would ideally happen when the lake is full; an excavation project would take place when the lake was dry.

“We have a substantial scope of work,” Natural Resources Manager Bob Hill told the San Luis Obispo City Council on Tuesday.

The consulting firm, MNS Engineers Inc., will also handle environmental studies and permitting, a “robust” public outreach process with property owners and community groups to discuss the possible options, and conduct a survey to gauge whether there is voter support for an assessment district to pay for a project, according to an agreement approved by the council.

Despite some lobbying last year from residents to act quickly and accelerate a plan to dredge the lake, the council set a goal to have a project ready to start by June 2017, at the end of the city’s 2015-17 financial plan.

$445,000 Cost of agreement between the city of San Luis Obispo and MNS Engineers, Inc. for the company to survey Laguna Lake, design three dredging and one excavation option, prepare cost estimates, provide possible types of financing and conduct public outreach.

City leaders have long talked about the best way to care for the lake, a naturally occurring body of water that has been altered over the years, according to the Laguna Lake Natural Reserve Conservation Plan adopted by the council in July 2014.

In the 1960s, Prefumo Creek was rerouted into the lake and the southeastern portion of the lake area was excavated and developed — creating recreational opportunities but also what the city has called a “long-term management challenge.”

As silt washes down from nearby hills, the lake continues to grow more and more shallow. The lake also went mostly dry in 1977 and 1991.

Plans to dredge the lake have been discussed for years, but the costly price tag has prevented it from happening. In 2009, the council reviewed a $5 million plan to dredge approximately 150,000 cubic yards from the lake over 10 years.

The conservation plan calls for dredging portions but also focuses on restoring eroded creek banks above the lake, continuing to remove sediment from the Prefumo Arm, and adding more sediment basins.

Hill said he expects to come back to the City Council this summer to present specific project alternatives, expected costs and financing options.

Financing could include grants, loans, a pay-as-you-go approach, a community facilities district that would assess individual properties to pay the project cost, or other options. An assessment district could encompass properties around the lake or in the larger neighborhood, or even the entire city.

Before then, there will be public workshops and other outreach efforts to the community, and Hill will give regular updates to the city’s Parks and Recreation Commission.

The contract with MNS Engineers drew only a few public comments Tuesday, including from San Luis Obispo resident Steve Barasch, who asked if some of the engineering work could be done in-house to save money.

“I know there isn’t a sense of an emergency right now, but it seems like a lot of resources are being spent to study something that could be studied internally,” he said.

Hill said the type of engineering done for fresh water dredging and excavation projects is fairly specialized and not the type of work the engineering staff typically handles.

Cynthia Lambert: 805-781-7929, @ClambertSLO