Better Drainage and Odor Control for Your Barn

Clear the swamp

Clear the swamp

When rain water begins to stand for long periods of time, it is time to think about improved drainage.
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Drainage problems around the barn and paddocks create a sloppy mess. Poorly drained areas collect stagnant water, which can become a breeding ground for pesky, disease laden insects.

Drainage problems also plague the interior of the barn, specifically in stalls where trapped urine builds to noxious levels.

Fortunately, barn owners have several options to alleviate drainage issues around the stable.

Divert water away from the barn

In most scenarios, barns experience the most significant drainage issues during or after a rainstorm. Water runs off the roof and other hard surfaces, such as an asphalt driveway, and collects in low spots around the barn, lingering until it is able to dissipate.

The first, least expensive remedy involves digging a trench drain or creating a swale. “A diversionary drain or a swale in the hill will direct water one way or another,” said John Blackburn, President of Blackburn Architects, P.C., “where it can be channeled into a retention pond, a stream or field and recycled back into the ground.”

A second, also inexpensive solution is to install gutters and downspouts along the roof line. With gutters and downspouts, “the water can be directed away from the edge of the barn to a French drain,” he explained.

Cross section of a french drain

Cross section of a french drain

Barn roof run-off is a particular problem. Constructing a french drain can help move the excess water away from the paddocks.
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A French drain is a trench lined with gravel and sometimes includes a perforated pipe. The gravel or perforated pipe captures surface and/or groundwater and directs the water away from a specific area, alleviating puddles.

“If the style of the building doesn’t accept gutters, a French drain around the drip line could capture the excess water and direct it away from the barn,” he said.

Permeable surfaces including pea gravel, stone dust, or manufactured permeable pavers can alleviate drainage problems. These surfaces allow water to seep back into the ground to lessen the volume of runoff.

Barns built on low lying ground with a high water table present a different challenge. These areas are naturally swampy and wet. A sump pump designed to draw water from one area and move it to a completely different location may be the only alternative available.

Eliminating odors

Poor drainage in the barn can lead to penetrating odors and potentially harmful respiratory problems. “(It) is particularly bad for foals because they are close to the ground,” Blackburn noted.

Stall flooring plays a significant role in drainage and odor accumulation. A clay base is dense, trapping urine rather than allowing it to seep into the soil.

Excavating along one wall and installing a perforated drain pipe may help. The perforated pipe allows water and urine to collect in the pipe, and when installed correctly, with a slight pitch, the liquids are directed outside.

Editor's note

Stone dust or sand as a stall base should be covered by rubber mats to avoid ingestion by horses. Ingestion of excess stone dust or sand may lead to colic.

If that does not solve the problem, another option is to remove the clay surface and replace it with a porous material such as stone dust or sand. Installing a perforated drain pipe in this scenario is also beneficial. “It is more expensive,” he noted, “but you can come in (and) flood the stalls to wash out urine and eliminate odors.”

Blackburn prefers popcorn asphalt and recommends its use to create a base inside stalls. “Popcorn asphalt is very porous. It drains well and is a good surface for stall mats,” he explained. With this type of flooring, the stalls can also be flooded to cleanse and remove urine and odors.

Ideally, if the budget were available, Blackburn suggests the installation of concrete slabs, with a center drain system. The drain allows for flushing and cleaning and the concrete slab provides a firm base for rubber mats or interlocking bricks to be placed on. “It’s more expensive, but a nice firm base. It avoids shifting of materials by stomping hooves,” he added.

Improving stall flooring is one aspect to reducing odors and improving drainage. Increasing ventilation in the barn is equally important.

Vents placed strategically along a roof line, known as vertical ventilation, encourages warm air to rise and exit the structure in strategic locations. “Better vertical ventilation and ridge vents along a roof line are good for ventilation,” Blackburn said.

Horses produce a significant amount of humidity through their body heat. The excess moisture builds in the winter months when barn doors are kept closed.

“You don’t want a barn to be drafty, but it needs to be well ventilated in all types of weather,” he explained. Installing ridge vents and encouraging vertical ventilation prevents cold winter winds while simultaneously providing an escape for excess moisture.

Blackburn’s firm has designed over 100 barns and each facility includes vertical ventilation. “We have not had one complaint about odor,” he said.

Sunlight is a critical component for keeping odors at bay. "Gases from urine thrive in dark, damp areas and the result is the pungent odor," he added. The odor seeps into the stone dust or soil flooring and lingers. Dutch doors are good too because they allow in low air and sunlight at the same time.

Easier chore time - Healthier horses

Improving drainage around the barn and eliminating odors from accumulated urine require planning and budgeting.

Determine which project is most feasible and tackle one upgrade at a time. The investment will be worth it—your horses will be more comfortable and you will not miss struggling through clumpy mud at chore time. Chore time inside the barn will be more enjoyable when the powerful odors that once chased you out have been chased out by proper ventilation and sunlight.

Dig deeperTM

Learn more about the construction of a French Drain to improve barnyard drainage.

About the author

Katie has been a freelance writer since 2001 and has more than 250 bylines to her credit.  In addition to writing for equine publications, she also writes for landscape, general agriculture and business publications.

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