Tragic fires can occur anywhere, anytime. Having ready access to an ample supply of water is critical in an emergency. Large cities provide pressurized hydrants for use in fighting fires. In rural areas, however, small water systems may not have enough water in reserve to fight a fire. Private wells can seldom provide the necessary flow for firefighting. Ponds, streams, and even wastewater treatment lagoons can be considered as a source of water to combat a fire.
Dry hydrants provide an easy access to fill tank trucks regardless of weather. A dry hydrant is a non-pressurized, low-cost pipe system installed along the bank of a body of water. The top of the pipe extends above the ground next to a body of water and the bottom of the pipe extends down into the water. A minimum of two feet of water must be maintained over the bottom of the pipe to assure year-round water supply.
The materials needed for a dry hydrant include: 6-inch (or larger) schedule 40 PVC pipe, hose connection compatible with local fire equipment, two 90-degree or 45-degree elbows, and a strainer with cap. The vertical dimension is the most limiting. Water cannot be lifted by suction greater than 20 feet. The hose connection must be positioned 2 feet from the ground so it is accessible year-round, even in snow. Therefore, the vertical length of pipe should extend down to a depth below frostline but no deeper than 18 feet. Less than 10 feet is preferred. The horizontal section of the pipe extends out from the bank and into the water, secured 2 feet up off the bottom to avoid clogging with mud. The pipe should be at least 2 feet below the anticipated water surface during low water conditions to assure enough water to fight a fire. The intake must be covered with a screen to keep debris out of the pipe.
Cost to install a hydrant vary with the length of pipe used along with the labor and equipment needed for excavation. To bring costs down, some groups provide the labor as a community service. The average cost of a dry hydrant ranges from $500 to $900.
Easy access is critical during an emergency. The hydrant should be well marked and next to an all-weather road. Access to the hydrant must have a minimum width of 12 feet and a maximum grade of 8 percent. Place a sign next to the hydrant. Remember, the area may be wet or even icy when it is needed most, so consider placing gravel or other paving between the road and the hydrant.
Dry hydrants require regular maintenance. Each hydrant should be inspected quarterly. Clear away any trees and underbrush that may make it difficult to locate or access the hydrant. Also check for aquatic plants or silt that could clog the screen. Backflush the hydrant quarterly and conduct a pump test. Regular inspections offer a great opportunity to train new fire department personnel. If a dry hydrant is located on private property, get written permission at the time of installation to access for inspections and emergencies.
The benefits of installing dry hydrants at bodies of water in and around a community include:
Plan ahead and install dry hydrants as new ponds are constructed. It is always simpler and cheaper to install a dry hydrant as the pond is being built.
National Fire Protection Association. Standard on Water Supplies for Suburban and Rural Fire Fighting. NFPA Standard 1231.
Natural Resources Conservation Service. Dry Hydrants-235. Ohio Engineering Standard #235.
This project is supported, in part, by the Ohio Small Community Environmental Infrastructure Group.
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