Preventing Water Pollution on Your Horse Farm

Tammy Brewster-Barnes, MS, extension associate, spoke to students, veterinarians, farm owners, and horse enthusiasts about horses and the Kentucky Ag Water Quality Act at the 2019 University of Kentucky Equine Showcase, held Jan. 26 in Lexington.

She covered water-quality issues relating to horse farms, as well as best management practices (BMPs) for preventing water pollution on or near farms, creating a water and soil conservation and nutrient (manure) management plan, and accessing resources available to help landowners comply with the Kentucky Agricultural Water Quality Act (AWQA).

The Kentucky General Assembly passed the Kentucky AWQA in 1994 with the goal of protecting the surface and groundwater resources from pollution resulting from agriculture and forestry activities. The act promotes practical natural resource management systems that protect Kentucky’s waters and complies with government rule and regulations. It mandates that landowners of 10 or more acres who apply plant available nutrients or who export manure must develop and implement a nutrient management plan as part of their agriculture water quality plan.

Brewster-Barnes said agriculture, as an industry, is a significant source of nonpoint water pollution—meaning runoff from eroded pastures, manure piles, fertilizer application, and concentrated animal waste. These pollutants frequently enter the watershed through agriculture related activities and can have devastating impacts on both the environment and horse heath.

In terms of water quality, “farmers have the biggest opportunity to make the biggest changes,” she said.

The AWQA emphasizes the importance of using effective and economic BMPs to create a water quality plan to reduce and prevent water pollution.

The Kentucky AWQA states that BMPs establish the minimum acceptable quality levels for planning, siting, designing, installing, operating, and maintaining agriculture and silviculture facilities and operations. Brewster-Barnes said BMPs are dependent on the focus of the agricultural activities on the property (i.e., farming the land or raising cattle) as well as water bodies on or near the farm, the land slope, and erosion potential, which all vary from site to site.

Horses and Water Quality

She said horse owners’ biggest concern relating to water quality is the introduction of excess phosphorus and sediment into Kentucky’s creeks, streams, and rivers. Horses are unable to digest certain forms of phosphorus, so it is commonly added into their diet via concentrates and supplements. When this phosphorus is fed in excess, it is excreted in the manure and can end up as nutrient runoff, which can upset the balance of the aquatic ecosystems downstream.

Phosphorus in manure and commercial fertilizers can be utilized by plants, bind to the soil, or become water-soluble when soil concentrations are too high. Meanwhile, sedimentation in Kentucky’s waterways from erosion due lack of land cover carries soil-bound phosphorus into the water. Then, aquatic plants and algae utilize the phosphorus, which results in blooms. When these plants and algae die, however, the water is depleted of oxygen, which negatively affects water quality and could result in fish deaths.

Specific horse industry BMPs vary among farms, but their implementation can help reduce water pollution caused by horses. Some examples are good pasture utilization and management, soil testing to determine nutrient concentrations prior to applying fertilizer, proper manure application on fields (which includes proper set-back distances from water or sink holes), proper manure storage and composting, and refraining from mowing near creek and pond edges. Brewster-Barnes also recommended owners use fencing to keep horses away from streams, sinkholes, ponds, forestland, and eroded areas.

She also said certain plants can help mitigate erosion near water sources and create a riparian zone to filter pollutants from pastures before they enter streams, ponds, and sinkholes.

“Let plants and grasses do their job,” she said. “That’s going to be your filter system.”

Learn more about riparian areas at

Additional Benefits

Complying with the Kentucky AWQA has many benefits for farm owners, Brewster-Barns said, including the ability to participate in cost-sharing programs such as the Kentucky Soil Erosion and Water Quality Cost Share Program, the Natural Resource Conservation Service’s Environmental Quality Incentives Program, and others. These programs can help farm owners with the costs of implementing BMPs to divert runoff and improve existing pasturelands.

In order to participate in cost-share farm owners will likely need to provide a Kentucky agricultural water quality plan; if the property stores manure, a nutrient management plan; a practice plan or goal; and a completed application.

Brewster-Barnes encouraged farm owners to think critically about their properties and identify if they had any issues, such as manure handing problems, erosion, or low crop or hay yields. Then, she said, they should consider what aspects they could improve upon to boost their property’s productivity and subsequently work on a nutrient and water quality management plan.

The UK Department of Biosystems and Agricultural Engineering Department says there’s no required frequency for plan updates. Brewster-Barnes recommended reassessing plans every three to five years and/or every time they make significant changes related to plans to ensure they remain up-to-date.

She also emphasized the importance of using resources available to local farms through their county’s Cooperative Extension Service or Conservation District Office. These professionals are familiar with the act and the statewide plan, as well as with how to implement plans at farms, she said.

“I do not look at the Kentucky Ag Water Quality Act like a regulation,” Brewster-Barnes said. “I look at it like a tool.”

The UK Biosystems and Agricultural Engineering Department offers planning tools for landowners to assess their operations and identify BMPs to be included in their water quality plan at

Samantha Geller, a senior double-majoring in equine science and management and environmental and sustainability studies, is a communications intern with UK Ag Equine Programs and the Gluck Equine Research Center.