DNR explains CAFO permitting, monitoring and limits of water-focused authority

Victoria Ziegler, the state Department of Natural Resources’ CAFO permanent program coordinator, told Portage County’s ad hoc advisory committee on industrial livestock operations that CAFO permits are water-quality tools and do not grant the agency authority over odor, traffic or animal welfare.

"These permits are water quality protection permits," Ziegler said, adding that "they are not odor, siting, animal welfare, noise, [or] traffic issues." She said a CAFO is generally an operation of about 1,000 animal units or more and that the DNR’s WPDES permit implements EPA’s Clean Water Act delegation to Wisconsin.

Ziegler summarized the permit application and review process: WPDES permits run for five years; applicants file electronically through the department’s ePermitting system and must include animal-unit calculations, an aerial map, a five-year nutrient management plan (NMP), documentation of 180 days of liquid manure storage, and engineering plans or evaluations for any reviewable structures. The department performs a technical review, conducts site inspections, drafts a permit and issues a public notice and a typical 30‑day comment period before making a final decision.

On technical standards, Ziegler said reviewable structures — equipment that handles, stores or transfers manure or process wastewater — must meet the department’s code (NR 243) and applicable NRCS standards. Engineering plans for new reviewable facilities must be stamped by a professional engineer and are subject to a roughly 90‑day DNR review for approval.

She described discharge limits imposed by CAFO permits as effectively "zero discharge" from the production area under normal conditions and noted storage and design expectations intended to prevent runoff: "All our structures on CAFOs are designed to collect the 25‑year, 24‑hour storm," which she said is about a five‑inch rainfall event.

Ziegler also covered nutrient management and monitoring. CAFOs must submit annual reports and NMP updates, conduct manure sampling for nitrogen and phosphorus prior to land application, and perform periodic soil sampling (she said soil sampling is required every five years). The DNR conducts compliance monitoring through site visits, application audits and production-area inspections; staff respond to citizen complaints and document noncompliance.

On enforcement, she described stepped enforcement that begins with voluntary compliance, moves to a notice of noncompliance and a notice of violation if problems persist, and — in the most serious cases — can lead to referral to the Department of Justice. Ziegler provided program averages: about 40 notices of noncompliance and roughly 14 notices of violation annually, with one to three DOJ referrals each year for the roughly 344 permitted CAFOs in Wisconsin.

Committee members pressed Ziegler on specific issues including what triggers a permit modification (she said a 20% herd increase or an additional 1,000 animal units typically prompts a modification review), whether the DNR verifies land‑owner permissions for spreading (the department does not routinely verify leases unless questions or complaints arise), and winter spreading restrictions (liquid manure surface application on frozen ground is prohibited except when injected or immediately incorporated; some county rules may be stricter). Ziegler urged committee members to use DNR’s public resources and the ePermitting site to review permit materials and application documents.

The DNR presentation framed state permitting as narrowly focused on protecting water quality and as relying on a mix of producer self‑reporting and periodic DNR inspection and enforcement to maintain compliance.