Published Dec. 11, 2011, in the Wyoming Tribune Eagle, “Plan to refresh Lake Minnehaha would benefit park visitors, including birds.”
2014 Update: The lake has been deepened and the island removed. Specially trained dogs have been hired to scare the geese away. This last summer, the geese seem to have relocated to the lakes out at F.E. Warren Air Force Base. I haven’t heard whether the lake smells better.
By Barb Gorges
What stinks at Holliday Park in the summer?
The waters of Lake Minnehaha, at 6.5 surface acres in the middle of the park, are stagnant. There isn’t enough movement and so it provides a perfect habitat for blue-green algae. In hot weather, it dies and produces the putrid smell.
This particular algal species can at times be toxic, killing dogs that drink it or sickening people coming in contact with it. It spreads on the water surface and blocks sunlight that would otherwise encourage growth of healthy organisms. Storm water runoff brings in more gunk and debris.
Teresa Moore, Planning Manager for the Cheyenne Parks and Recreation Department, invited me to read the recently compiled report from Ayres Associates proposing how to clarify the water.
- Deepen the lake, from 3 feet to 8 or 9, with gradual slopes where there are now eroded banks. The island would not be rebuilt.
- Instead of aerators, which have been tried before, install a SolarBee. The 300 already installed nationwide show they are effective in circulating water, which creates enough surface turbulence to keep blue-green algae from growing. It would be in the middle of the lake and, as the name implies, powered by attached solar cells.
- At the storm water inlets, put in SNOUTS, ingenious technology that collects gunk in an underground vault before it can go into the lake. Vacuuming the vault once a year would be easier than the maintenance department’s current methods.
- Develop wetlands– cattails and rushes–by the inlets to catch remaining sediment so it doesn’t fill in the lake over time.
- Route “reuse” (treated waste) water through the lake. Cheyenne has plumbed itself to use it for irrigating other parks, cemeteries and athletic fields. The water would constantly flow through new inlets and out through a new automatic outlet (the current one has to be adjusted by hand), helping prevent blue-green algae growth. Reuse water would also irrigate Holliday Park.
From my birdwatching observations at the park, blue-green algae doesn’t affect the Canada geese. By the middle of last June, I was counting 200 of them, including 40 goslings.
The adults were molting and unable to fly. By fall, wing feathers grown back in again and daily numbers (between 8 and 9 a.m.) were running 100-150. They spend time in the water, but mostly they graze the grass.
There also are a few dozen mallards and domestic ducks, three dozen white or gray domestic geese and occasional wild visitors: wood ducks, redheads and shovelers.
Removing the island would make me sad, but it would remove the major location for goose nesting. By all standards, especially the standards of people trying not to step in goose poop, there are too many geese.
By clean water standards, there is too much nitrogen in the water, some of it from goose poop. Removing the island hatchery could encourage wild geese to disburse and nest elsewhere. The island is not used as a refuge from potential predators. When the geese feel threatened, they, and their goslings, head for the water, not the island.
The black-crowned night-herons used to nest in the island’s trees, but when the big trees disappeared, they moved to the big cottonwoods to the north. Pelicans sometimes rest on the island in spring and summer, but I’ve seen them enjoy island-free lakes on F.E. Warren Air Force Base and they like a thick stand of cattails just as well.
What attracts the non-water birds are the trees. If willows are added to the shoreline, as suggested in the plan, over time, they will make up for the loss of the scrubby foliage on the island.
All of the improvements would clarify the water, allowing other organisms to grow, including the food chain that leads to fish. We might see more of the fish-eating bird species that we see at Lions Park, like the grebes.
All together, the proposed improvements would have a positive impact on birds—and other park users.
So when can the digging begin? As soon as $1.5 million can be found. The city does not have a budget line for construction in the parks, though there are many repair and improvement projects needed.
Park damage just doesn’t get the same respect a pothole does.
Because the Holliday Park project involves water and engineering, Teresa said there are some funding options. She’s an expert when it comes to writing grants, so if you have ideas, contacts or appropriate funding sources, be sure to contact her at 638-4375, or firstname.lastname@example.org. If you have comments on other park topics, please call 637-6429.