CHENEY, Kan. (KSNW) — Cheney State Park manager Shayn Koppes is preparing for the busiest holiday of the year at the lake: Memorial Day. He says an estimated 40,000 people will be enjoying their extended holiday weekend out on the lake in 2023.

Koppes also says now is the time harmful algal blooms are starting to develop in earnest. While Cheney Lake is currently not under any watch or warning, he says it’s always a good idea to know the signs before you go.

“It looks like somebody dumped green paint into the water is what it looks like, so if you do see something like that, you need to report it to either us at the park office or to KDHE’s website,” Koppes said.

Koppes says roughly 10 officers will be on patrol over the holiday—available to test the lake for blue-green algae.

“If we do get to a warning status, we will close our designated swim beaches, but as far as within the lake, it’s kinda, it’s at your own risk,” Koppes said.

Koppes says harmful algal blooms (or HABs) are the result of agricultural runoff entering the lake. Local nonprofit Cheney Lake Watershed, Inc. currently works with 300 farmers near the lake to minimize runoff.

“By infiltrating that water into the soil, you’re keeping it back in the field where it can grow crops, and those crops in turns have roots that will infiltrate more water, so it’s really a good, it’s really a win-win situation for the farmer out there,” Howard Miller, outreach coordinator for the Cheney Lake Watershed, said.

However, Miller says because those recommended practices can be cost-prohibitive, only 30-70% of farmers in any given area of the watershed follow them.

“Somebody going from what we consider conventional farming, where they’re, they’re tilling, they’re using conventional farm equipment, and they have to transition to no-till, that requires a different implementation, it can be hundreds of thousands of dollars,” Chloe Gehring, Project Manager of the Cheney Lake Watershed, said.

Koppes says although there’s no way to forecast when an algal bloom can strike, if you choose to swim or fish this holiday weekend, stay alert.

“Even if you don’t think that you’re in the blue-green algae, but you think it’s a possibility, just make sure you take extra precaution,” Koppes said.

For a current list of Kansas lakes under watches and warnings, head to the Kansas Department of Health and Environment’s website.