What else will surface at Echo Park Lake?

So far there have been no dead bodies, no safes stuffed with soggy cash, no rusty stolen cars.

The only things exposed by the receding water at Echo Park Lake have been shopping carts, 55-gallon steel barrels, a parking-enforcement “boot” and lots of skateboards.

But who knows what is still hidden in the muck at the bottom of the 13-acre lake, soon to be dredged and outfitted with a leak-proof clay liner?

Officials say that leaks once required them to replenish the lake with valuable drinking water. The sludge at the bottom will be hauled to landfills, depending on what’s in it. The sediment is 5 feet deep in places, brownish, greenish and chalky gray, laden with roots and branches.

The draining began the first week of September and continued through last week. Twenty-one million gallons of lake water were pumped into the city’s sewer system. The lake and surrounding parkland are to remain fenced off during the two-year, $64.7-million makeover.

The lake was emptied in two stages, with water lowered just enough in the first phase to allow biologists to capture fish and relocate them to MacArthur Park Lake, while about 95 turtles were turned over to the California Turtle and Tortoise Club and put up for adoption.

Geese and ducks were not relocated, although four small temporary ponds were constructed for waterfowl that didn’t fly to other lakes.

The lake upgrade will include development of four acres of wetlands at its edge and paths made of pervious material that will replace the park’s old paved walkways.

Originally constructed in 1868 for drinking water storage by the Los Angeles Canal and Reservoir Co., Echo Park Lake has more recently functioned as a storm drain detention basin as well as a park site and wildlife habitat.

Although the lake was drained in 1984, the Regional Water Quality Control Board labeled it “an impaired water body” in 2006. Algae, ammonia, copper, lead, PCBs, low oxygen levels and trash in the tepid water were killing off the lake’s signature lotus plants.

On Monday, geese gathered in their fenced-in temporary ponds and a few ducks paddled in a small pool of lake water remaining near the boathouse.

At noon, a coyote could be seen loping across the empty lake bed, eyeing the ducks and searching for dead fish. George Magallanes, an aide to Los Angeles City Councilman Ed Reyes, said the coyote killed two domestic geese over the weekend, apparently after slipping through a fence knocked down in a Saturday traffic accident on Echo Park Avenue.

Officer Gregory Randall, a wildlife specialist with the city’s Department of Animal Services, patrolled the lakeshore with a paintball gun, hoping to scare away the coyote.

Workers, meanwhile, began spreading lime on the lake bed to deodorize sediment fouled by decades of waterfowl droppings. Sweet.

bob.pool@latimes.com