Delays Repairing Lakes Cause Costs to Balloon
By Carol Dimmick
Ten years after voters approved a $76 million bond measure to restore Golden Gate Park to its former glory, work has finally gotten underway to rehabilitate North Lake, but the delay has proven costly.
In fact, it will cost taxpayers triple what a report by the SF Department of Public Works estimated it would cost to fix the problems in 1994.
According to the report, which studied 12 bodies of water in Golden Gate Park as part of a Master Plan for a 1992 bond measure, it would take $1.4 million to restore the lake. Today the same project will cost the City just more than $4 million.
North Lake is the first lake to undergo the breadth of restoration recommended in the 1994 report and the only lake rehabilitation project that will be paid for out of 1992 bond funds. It is also the only lake the city intends to restore using a comprehensive approach.
Critics claim poor planning and the years of neglect have made the lakes unhealthy for wildlife.
With the exception of Elk Glen Lake, the park's man-made lakes in the Chain of Lakes in Golden Gate Park were constructed more than 100 years ago with very shallow bottoms. Over time, the lakes have become shallower and more polluted from years of sediment accumulation, debris and algae.
The 1994 report said that, with the exception of Stow Lake and Lily Pond, the lakes were leaking into the ground at a rate of more than 500,000 gallons of water per day.
The combination of shallow bottoms and leakage has caused the quality of the water in almost all of the lakes to deteriorate to the point where they are unsuitable for wildlife.
To restore the lakes, the report recommended a comprehensive approach that includes hardening the perimeters, removing, draining and disposing of sediment, and deepening and sealing the bottoms with clay. It also recommended installing expensive aeration equipment to ensure that the water remains healthy.
North Lake project underway this summer
North Lake was the first lake constructed as part of the Chain of Lakes Project in 1898. It is one the most natural-looking lakes in Golden Gate Park. It has six small islands planted with exotic vegetation and a levee that divides it into two segments.
The lake, along with South Lake and Middle Lake, underwent minor reconstruction in 1983, which included vegetation removal and general sediment excavation. Bentonite was also applied to the lake's bottom to prevent leakage.
By 1990, the north end of the lake was leaking again and had to be sealed again. It continues to leak today. The shoreline of North Lake is severely eroded, contributing to the deterioration of the water quality and making it difficult for wildlife to inhabit the lake.
Recently, the SF Recreation and Park Department took a series of steps to prepare the North Lake for restoration. One of first was to remove invasive tule vegetation and introduce additional landscaping around Middle Lake to provide habitat for wildlife expected to be displaced during the restoration process.
In September work began to dredge the lake to increase its depth up to eight feet in some areas. Dan Mauer, project manager, says that the restoration encompasses all the recommendations contained in the 1994 report, including lining the bottom with clay and installing a complex pipe irrigation system to keep the water clean and habitable for wildlife.
Lakes ignored while bond money dries up
When voters approved the bond in 1992, which included restoring of all of the lakes in Golden Gate Park, restoration plans were put on hold after it was discovered that blueprints for the first priority the park's aging sewer, irrigation and electrical systems had to be reproduced before work could begin.
"We didn't have drawings or plans to work from and we had to do aerial flyovers to get an accurate picture. We had to figure out what was there," explained Shannon Maloney, a project manager for the Department of Public Works.
In 2001, the city scrapped plans to restore Middle Lake and South Lake after the community raised objections to removing trees and voiced concerns over other features of the project, according to city officials. Most of the funds were spent on other projects in Golden Gate Park.
Today the lakes have deteriorated to such an extent that maintenance work is well beyond the capability of the park staff, according to some park supervisors.
"Most of the problems are beyond us from a maintenance standpoint. We are now dealing with emergency problems in an emergency way," said one park supervisor who declined to be identified.
Stow Lake riddled with garbage and debris; boat concession loses
Stow Lake, the most spectacular lake in Golden Gate Park, was built in 1893 and was originally designed for leisure boating and as a promenade for horse drawn carriages.
According to the 1994 report, Stow Lake had a sediment deposit of 35 inches, well above the other lakes, which ranged from low of 3.5 inches in Lily Pond to 17 inches in Elk Glen Lake.
The report called Stow Lake "a demonstration of the great impact upon water quality of aquatic life and waterfowl, intimate public interface, dense overhanging vegetation and poor circulation and erosion."
Today debris in the lake has caused the water to deteriorate to the point that the owners of the boat concession stopped renting electric boats to tourists last summer.
"We tried for the longest time to deal with it. Finally, it came to the point where we were having to give refunds, so we only rent pedal and rowboats now. They are easier to maintain and you can use the oars to push off when you get stuck in the debris," said Jeff Fones, who manages the boat concession at Stow Lake.
Fones also said that when the city turned off the generator at Huntington Falls to save money during the recent energy crisis, the water quality deteriorated even further.
Gary Hoy, manager of the Recreation and Park Department's Capital Program, confirmed recently that the city intends to dredge Stow Lake and do some work around the perimeter, but he said funds were not available to do the type of restoration recommended in the report.
Algae bloom kills fish in Spreckels Lake
In June, workers at Golden Gate Park responsible for maintaining Spreckels Lake, the most urban lake in the park, became alarmed when hundreds of dead fish began washing up on the shoreline.
Unusually warm weather turned the second largest lake in Golden Gate Park into a death trap for fish when the hot weather triggered an algae bloom that depleted the lake's oxygen supply.
As far back as the 1994 report, the water quality in Spreckels Lake was described as "poor, particularly along the eastern edge where natural winds blow the debris and surface algae."
According to Hoy, if the City gets the money it anticipates from the $35 million state bond voters passed this year the lake will be dredged. The City is also considering installing aerating equipment if money becomes available.
Hoy said the City is looking at ways to improve the water at Lily Pond, but he confirmed that the rehabilitation projects envisioned today for the lakes fall far short of what the report recommended in 1994.