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Municipal Technical Advisory Service (MTAS)

Correcting Deficient Fire Flows

Reference Number: MTAS-1898
Reviewed Date: 10/02/2023

TDEC Rule 0400-45-1-.17(18) provides a fire chief with justification to request improvements in the water system. The regulation does not prevent the fire department from using a deficient fire hydrant (e.g., to fill tanks), but it does prevent the fire department from using a deficient fire hydrant with the fire apparatus pump engaged, which may result in inadequate fire flows and a poor outcome in firefighting operations (i.e., increased property loss). Once the fire department has identified at-risk areas with deficient water supplies for firefighting, the fire department should request of the water department, and any other departments, agencies, or entities that would be involved in decision-making and funding, a plan to upgrade the water system to provide adequate water for the protection of life and property. An inadequate water supply for fire protection makes it difficult for a community to get a good ISO rating for lower property insurance rates.

The TDEC regulation provides fire departments with a way to identify hydrants with deficient fire flows so that the fire department does not use the deficient fire hydrant if another hydrant with adequate fire flows is within a usable distance of the fire. The regulation requires that deficient fire hydrants be marked with a red top to denote that the fire hydrant flows less than 500 gallons per minute, thus identifying the hydrant as a deficient fire hydrant for responding firefighters.

Once areas of a community with deficient fire flows are identified, the fire department and water utility should use a cooperative approach to create and implement a plan of corrective action. The common goal for both the fire and water department should be to protect the water system and public health while delivering adequate fire flows to the entire community. Improving the water system can be costly, requiring engineering studies and design work, which takes time. In addition, the utility must find funding sources for the improvements. Therefore, correcting deficient flows will take time, but the sooner everyone develops and approves a plan, the sooner the community will enjoy the benefits of an adequate water supply for fire protection purposes.

Improving the water system, installing larger water mains, replacing older/smaller water mains, and installing fire hydrants is expensive. Smaller communities may be eligible for community development block grants (CDBG) to provide financial assistance in improving the water system for fire protection purposes.

The CDBG program in Tennessee.