Wells & Rural
For Farms Considering Manure Gas, Start With a Clean-Water Map
A federal tax credit may encourage more manure-to-gas projects, but farms should first trace how rain moves across roofs, yards and waste-handling areas.
Reviewed: September 21, 2026
New federal guidance could bring more attention and investment to farm-based biogas. Circle of Blue reporter Brian Bienkowski writes that new IRS guidance on manure-derived gas confirms that gas extracted from livestock manure qualifies for a federal clean fuel tax credit.
That is a tax and energy development. For rural water, however, it raises a practical question: Before adding equipment intended to manage manure, does the farm know where clean rainwater goes?
Anaerobic digestion can change how manure is handled, but it does not eliminate the need to manage runoff across the rest of the property. Roofs, gutters, yards, lanes and low spots still determine whether relatively clean rainfall is directed away from work areas or allowed to mingle with material that must be managed.
Begin with the roofs
A farmstead water map can start at each roof edge. Mark every gutter, downspout and place where water falls directly to the ground. Then follow the likely route toward a ditch, field, drain, ponding area or manure-handling zone.
After hail or strong wind, use a ground-level checklist before making decisions:
- Look for gutter sections that have pulled loose, twisted or begun spilling water beside a foundation.
- Check downspout outlets for displacement, blockage or erosion.
- From the ground, note visibly lifted roofing, missing pieces or damaged vents. Do not climb onto a wet, steep or storm-damaged roof.
- Inspect accessible attic areas for damp decking, wet insulation, stains or daylight where it was not previously visible.
- Photograph the building from several sides, then take closer pictures of visible damage and water paths.
- Record the storm date and the date each condition was noticed. Review the property insurance policy and contact the insurer promptly enough to learn its reporting and documentation requirements.
If the roof cannot be evaluated safely from the ground, or if water is entering the building, it may be time to schedule a storm damage roof inspection. A roofer can assess surfaces and flashing that cannot be judged reliably from the yard.
Keep three kinds of water separate on paper
The useful map distinguishes water by where it has been. First is roof water, which begins as rainfall on a relatively clean surface. Second is yard runoff, which may cross lanes, feed areas or equipment routes. Third is wastewater or manure-contact water that belongs in the farm’s waste-handling plan.
The categories are less important than the routes. Draw arrows showing where each flow begins, what it touches and where it ends. Pay special attention to places where clean roof drainage enters a work area. That connection can increase the volume of water that must be handled even when the new energy equipment performs as intended.
Repeat the walk during a moderate rain if conditions are safe. Dry-weather observations often miss overflowing gutters, shallow channels and low spots that connect separate parts of a farmstead.
Do not confuse drainage work with drinking-water treatment
Farmstead runoff and household water quality are related planning concerns, but they are not the same problem. Redirecting a downspout does not establish whether a private well is affected. Likewise, a household treatment unit does not correct drainage around barns or manure infrastructure.
When a household is evaluating drinking-water treatment, the discussion should begin with the water source and the specific issue to be addressed. Local resources, including reverse osmosis specialists serving the St. Louis area, can help explain what that treatment method does and does not do. That conversation should remain separate from decisions about farm runoff and manure management.
FAQ
Do I need a roof inspection after a Midwest storm?
Not every storm requires a professional inspection. Begin with safe ground-level and attic checks. Call a roofer when there is visible damage, active leakage, displaced drainage equipment or an area that cannot be evaluated safely.
What photographs are useful?
Take wide views that identify the building and closer views that show the condition. Include gutters, downspouts, attic moisture and the ground where roof water lands. Keep the original files and a simple dated note.
Should the water map wait until a biogas project is designed?
No. A basic map can be prepared before equipment choices are made. It gives the farmer, project designer and other advisers a shared picture of existing flows and shows where questions remain.
The federal credit may make manure-derived gas more financially attractive. It does not answer the local water questions. Those answers begin with a walk around the farm, a camera and an honest map of where the rain goes.