Most Drainage Wells Closed Through Cost-Sharing

By Zoe Martin, Iowa Farmer Today

It seemed like a good idea at the time.

But, in the past 20 years, hundreds of ag drainage wells built in the early 1900s have been quietly, successfully closed — from more than 300 in Iowa down to about 48 this summer.

The wells were constructed to drain land with limited access to streams or ditches. They also carried bacteria, nitrates and, in some cases, household septic drainage straight to drinking water aquifers and the groundwater supply.

Testing for pollutants began in the 1980s.

Pressure from environmental groups in Iowa pushed the Legislature to make ag drainage wells illegal, said Michael Anderson with the water supply engineering section of the Iowa Department of Natural Resources.

“We didn’t want to punish farmers for decisions made by their grandparents,” he said.

So, to help spread the burden of closing them down, the Iowa Legislature in 1997 established the Agricultural Drainage Well Water Quality Assistance fund -- a 75 percent cost-share for individual or groups of farmers in drainage districts.

The DNR works with the USDA’s NRCS and Iowa Department of Agriculture’s Water Resources Bureau, which administers the fund.

Bureau Chief Jake Hansen said 300 of the wells built in Iowa still existed at in the late ’90s, mostly in North Central Iowa. The cost-share program has helped close 153.

Ninety-nine have been closed independently by landowners or deemed non-functioning. Twelve of the 48 remaining are in the process of closure.

That leaves 36 permitted working wells.

“Permits for those that remain run through 2019 or 2020,” Hansen said. “There’s a decent possibility those permits would not be renewed at that time.”

The details for each closure project vary. Anderson said the process starts with design bids from engineers.

Construction involves building a berm around the well, re-routing the drainage and blocking the well with a bentonite slurry-type material. 

It’s also typically capped.It’s material intensive, and the biggest engineering problem is setting up alternative tile drainage, Hansen added.

“The big thing you’re looking for as you set up alternative drainage: Will it work for the farmers involved or make things worse for neighbors?” Anderson said.

“You’ve closed the well, so there’s nowhere for the water to go anymore so it’s got to be conveyed somewhere.”

Some projects involve just one well. Ag department engineer Mike Bourland said his largest project closed 37 wells in a drainage district in Pocahontas County.

“The overall program average as far as the cost to the state of Iowa is around $91,000 per well,” Bourland said.

“That’s just our cost share on projects. The landowners provide the remaining 25 percent of project costs.”

Some are easy to close, others have issues that drag those costs higher, he said. Wells in shallow limestone areas can present unique challenges.

Some are so far from acceptable outlets they’re going to require significant alternate tiling, working around sand ridges, underground storage tanks or wetlands.

“We’re coming up on 90 percent of wells being closed. The ones that are left are going to be the ones most challenging to address,” Bourland said.

“There’s still work to be done.”

The first year of the fund in 1999, the Legislature appropriated $3 million. For six of the past seven years, it’s been about $1.5 million, Bourland said.

No money set aside for fiscal 2015.

Anderson said the DNR, NRCS and state ag department consider it a highly successful operation, especially compared with other states’ approaches.

“Minnesota took an 800- pound hammer approach and told farmers, ‘They’re you’re problem, fix them,’ ” Anderson said.

“In general, having agencies get on the same page and coach everyone toward a better situation is better than being heavy handed and fining people.

“We haven’t had much negative feedback,” he added. “Of all the things we try, it’s nice to have something like this that really works.”