COLORADO SPRINGS, Colo. -- City officials are using enzymes to prevent closing Prospect Lake because of the presence of blue-green algae in recent years, while still exploring a permanent solution to the problem.
Monday morning, on Independence Day, one boat and several jet skis were in use at the popular lake east of downtown; some boaters said that the lake wasn't as active as normal for a holiday because people may have thought it would be too crowded, or there was too non-motorized traffic in the water on a day reserved for motorized traffic only.
Earlier this year, officials canceled a plan to ban boating and other motorized watercraft at the lake so that an aeration system could be installed -- which would add oxygen to the water and limit the growth of the naturally-occurring algae.
That decision came after strong negative feedback from the public, including boat owners who said that their nearest option for boating is at the Pueblo Reservoir.
"I went to Pueblo one time when I moved out here in 2012, and the next weekend, -- and the next weekend, I was out here and I've been out here ever since," said Terry Sheehan while standing beside his boat.
The city's Parks and Recreation Department is looking at several aeration designs to determine which would work best for the lake and hopefully limit or avoid any reduction in boating.
A decision is expected late this month or early next month.
"We boat owners have spoken with experts about this," said Aaron Oelich. "If you put in an above-surface aeration system -- which are fountains -- that actually increases the water temperature because it's shooting and increases evaporation. And it's more costly to operate. So if you put in a sub-surface aeration system, it's more effective because you're pushing air instead of pushing water."
Oelich said that he hopes the final solution will increase safety for everyone who uses the lake, not just boaters.
The algae, a form of bacteria, often increases during warmer summer weather and can be harmful to people and pets if it grows quickly; stagnant water, hot weather and polluted stormwater runoff contribute to the blue-green condition.
Prospect Lake was closed for several weeks in the late summer and early fall of 2019 and 2020 because of the algae.
Parks and Recreation also is seeking assistance from Colorado Springs Utilities in determining whether water is leaking out of the lake; officials will determine whether the lake is losing water simply due to evaporation, or because of an undetected leak or seepage.
In 2005, officials drained the lake, installed a liner and refilled it after the water level began falling at an unacceptable level because of an apparent leak.
"I don't think it's a big issue," said Kim King, manager for Parks & Recreation. "But we've had some reports about it, so we'll check it out. We topped off the lake (added water) a month ago but has been hot."