By Joe Wilkinson
Iowa Department of Natural Resources
A mid-summer day at the lake? There’s the beach, canoeing, camping...maybe poking around a few fishing hotspots from the boat. Hard to beat in Iowa...or anywhere for that matter.
It’s a much different picture this season at Lake Darling State Park. Stake bed skeletons and other fish habitat stick out from the mudflats and the little bit of water in the basin. Still, the promise of what is to come makes it worth the wait.
The effort—some of it completed, some yet to come---is a testament to cooperation; between adjoining landowners, between landowners and the park, and within the Brighton community itself, recognizing the regional economic and recreational draw. Just as importantly, coordinators say the plan—in large part--can be duplicated across Iowa. That’s important, in a state with dozens of human-built ‘middle aged’ lakes which have hit 50, 60 and 70 years of age.
Just the lake reconstruction itself is huge in the state park, located an hour south of Iowa City where Washington, Keokuk and Jefferson counties meet. An extended dam and spillway system will replace the cracked, aging structure that impounded 302 acres of water when the park opened in 1950. Sediment washing in from the 12,500 acre watershed has reduced that to 267 acres now.
Dredging will peel back a thick, smothering blanket of silt. “Back in the ‘campground’ arm of the lake; you see reed canary grass (in the old lake bed). About 50,000 cubic yards of sediment will come out of that area of the lake,” notes Department of Natural Resources fisheries biologist Chad Dolan, standing between two of the work areas. “Move forward here (near the boat ramp/island area) with all this exposed sediment, another 140,000 cubic yards will be removed.”
But just removing sediment isn’t worth the considerable trouble...and expense...if decades of future fill float back in. That’s the ‘unique cooperation’ part that puts a smile of the face of Stan Simmons, who heads up the watershed project, a group effort between the DNR, the Washington County Soil and Water Conservation district and other agencies like the Iowa Department of Agriculture and Land Stewardship and USDA Natural Resources Conservation Service, and of course, landowners. “Private landowners own 90 percent of the draining area,” underscored Simmons, as he guided a bus tour of the watershed, explaining the project to Iowa Natural Resource Commissioners, and others involved with the project. “It was only through their cooperation and willingness that we get the land treatment that was so needed to take care of the sedimentation and other (water quality) problems.”
At one stop, Simmons points to a sloping field with a deep creek carving through it. When cattle were pastured there, debris and manure just flushed across Highway 71 into the park and, eventually, the lake. Now, the owner keeps cattle out and cuts the hay. The runoff issue is settled. On the other side of the gravel, a four acre pond lets silt from the adjoining 400 acres settle out, a mile from the lake. Same landowner, but here, Washington County agreed to build up the gravel road. A dam was created and the line of sight to the highway was improved. “A mutual benefit,” pronounced Simmons; a term used repeatedly on the tour.
North on the county blacktop, Simmons points to what he calls his ‘pride and joy.’ “This 22-acre pond drains 1,200 acres; 10 percent of all the water flowing to the lake,” he announces. “It took the cooperation of five different landowners.” At each stop, there’s a similar story; landowner opts for a pond, rather than grass waterway strips...maybe a CRP contract here...tile outlet terraces here...road culvert risers there. Several new homes show a little rural economic development, too.
Each ‘treatment’ helps keep silt out of the lake. They slow the movement of water, allowing sediment and nutrients (primarily excess nitrogen and phosphorus) to settle out. They basically filter that water as it makes its way toward the lake basin,” says Dolan. “You get a much cleaner lake. It benefits (more desirable) sight feeding fish. Their growth is accelerated.”
That fishing attracts anglers. The expanded beach and cleaner water attract other park goers. The spacious, year-old four season lodge – built on the fundraising efforts of the Friends of Lake Darling - attracts everything from family reunions to weddings. It all means money in the pockets of area businesses...and a focal point for residents, and former residents who come back to the Brighton area.
And, while the rolling topography presents local challenges and benefits, the message throughout the up close view of the watershed was that the mix of private and government involvement could be repeated across Iowa; with Simmons stressing, though; “without landowner cooperation, you won’t get anything done.”
Lake Darling Project
Outside the park:
12,500 acre watershed
71 different landowners
151 private land construction projects
Cost; $1,495,000; $1,072,000 cost share funding
31 private ponds
CRP signup, and continues
Many other ‘treatments’ before this project
Inside state park:
Reconstructed, expanded dam and spillway
Construction June ‘10, done June ‘11
11 erosion control ponds, 20 more coming
8 road culvert risers
300,000 cubic yards of dredging coming
6,300 tons of rock to ‘armor banks’
$4.7 million investment
Iowa Sportsman
http://www.iowasportsman.com/article.php/20090721160101804