Prince William Soil & Water Conservation District
By Kate Norris
Installing a Simple Outdoor Wash Stall
Getting your horse ready for a show or fair, rinsing away sweat after exercise, treating a wound, or just giving your horse a"day of beauty" is much more enjoyable when you have a properly functioning wash area. The following recommendations will guide you through the installation of an economical, practical, and environmentally-friendly outdoor wash stall, for five horses or less.
- Site Selection
Choose an area that is convenient to your barn and water source and has well -drained soils. The Conservation District can provide you with soils information for your property. Avoid placing the wash area where runoff will flood walkways, work areas, manure storage areas, or drylot paddocks. The best site is well away from ponds, streams, and wetlands-- at least 100 feet. The wash stall is designed to direct the majority of the wash water through the rock layers, but you should site your wash stall so that any surface runoff containing detergents, grooming products, or fly sprays can filter through a well-vegetated buffer in the surrounding area.
You'll need 4 railroad ties or landscaping timbers 8 feet in length and stakes to secure them to outline your stall, 2 sturdy fence posts on which you'll mount your cross ties, and your footing materials. Gather an 8 feet x 8 feet piece of geotextile/filter fabric, 3 tons of VDOT size #1 gravel for the base material, 1.3 tons of VDOT size #57 for the surface treatment, and an open weave rubber mat for your horse to stand on. You want your surface material to allow water to drain through it and into the rock layers below. A stall mat also provides a surface that is easy to clean manure off of and will prevent an impatient horse from digging through all your hard work when you run back to the barn for some conditioner.
Start by preparing the surface. You should remove the sod and top 12" of soil in an area approximately 7 ½ feet x 7 ½ feet (make your "pit" smaller than the area you will box in with your railroad ties so that the railroad ties can be placed at the original surface level). Box-in the wash stall area with your rail ties or lumber, securing it with spikes. Next add 8" of size #1 gravel, followed by 4" of size #57 gravel, and finally a rubber stall mat. Set two fence posts (w/concrete for better stability) on which you can attach cross ties, outside the wash stall. Now you're ready for the finishing touches such as an easily managed hose, a spray nozzle for controlling the flow of water, and a basket or other container to keep shampoos and sprays upright when not in use, preventing leakage into runoff water.
Promptly clean up any manure before it can run off or prevent water from draining through your gravel layers. Watch for signs of erosion between the washstall and grass buffer. Add gravel or reseed areas as needed to prevent soil loss.
A properly sited and installed wash stall should last for a long time and make giving baths or medical treatments more pleasant. Take the time to consider the water quality impacts before you begin. Additional planning and installation assistance is available from the Conservation District, including more elaborate designs for larger operations or for those with poorly drained soils.