Iowa's agricultural landscape is dominated by nearly 8,000 concentrated animal feeding operations (CAFOs), housing millions of animals that generate a staggering 110 billion pounds of manure each year. Despite this immense volume, the Iowa Department of Natural Resources (DNR) currently does not collect records detailing where and how much of this manure is actually spread as fertilizer, leaving a massive gap in environmental oversight.

This critical failing is highlighted by Gene Tinker, a former animal feeding operations coordinator for the Iowa DNR, who now operates his own farm. Tinker, who previously advised on livestock permitting and manure handling plans, contends that the DNR’s approach to regulation and data collection is severely inadequate. He points out that while hauling companies track manure application, Iowa law classifies these crucial records as "confidential," effectively preventing public scrutiny and accountability. Tinker argues that digitizing and making these records public would significantly aid the state's efforts against water pollution.

The consequences of this unregulated manure disposal are severe for Iowa's environment and public health. Excess nitrogen and phosphorus from manure runoff end up in waterways, leading to toxic algal blooms and dangerous levels of nitrates in drinking water. Ingesting nitrates can cause a deadly condition in infants, and numerous studies link exposure to an elevated risk of cancer, including methemoglobinemia, also known as "blue baby syndrome," which poses acute life-threatening issues for children. Iowa faces a nearly 50 percent increase in nitrate levels in its waterways, coinciding with one of the nation's highest and rising cancer rates. Furthermore, this pollution carries a substantial economic burden; Des Moines Water Works, for instance, spent around $10,000 daily this summer operating its nitrate removal facility and even enacted a lawn-watering ban due to spiking nitrate levels this summer.

Adding to the problem are Iowa's outdated agricultural rules, which haven't seen significant updates since the Animal Agriculture Compliance Act was first codified in 2002. Although facilities are required to submit manure management plans specifying application fields, DNR technical reviews of these plans occur only during random inspections or when new facilities seek construction permits. Records show that only about 7 percent of active plans were inspected this year. Tinker also criticizes the reliance on nitrogen demand calculations for crops that date back to the 1950s, instead of modern tools like the corn nitrogen rate calculator developed by Midwest scientists. Efforts to update these values faced resistance from agricultural groups concerned about reduced crop yields.

According to Tinker, the state has intentionally overlooked the problem, failing to modernize its systems. He stresses that while a public database exists for tracking submissions, there's no comprehensive system to aggregate data across multiple plans, making it impossible for the DNR to accurately quantify nutrient application statewide. Without transparent and verifiable records, the crucial "trust, but verify" principle is missing, leaving Iowans to bear the mounting costs and health risks of unchecked agricultural pollution.