Skip to Content
NASHVILLE.gov - Metro Government of Nashville & Davidson County, Tennessee NASHVILLE.gov - Metro Government of Nashville & Davidson County, Tennessee (Print logo)

Use the garden hose safely

What can I do to protect our drinking water from contamination?

Required Devices

You are required to install and maintain an appropriate backflow protection device.

  • Underground irrigation systems require a reduced pressure backflow device.
  • Pools, ponds, saunas, hot tubs, and above ground sprinkler systems may require a backflow device unless you are using the air gap method shown and described below.

Create an Air Gap

Picture: faucet with water flowing, Text: air gap, 2 inch diameter not less than 1 inch

Always create an air gap between the end of the hose or faucet and the water surface of your pond, pool or bucket when filling. This can be accomplished by securing the hose or faucet on a surface high enough to prevent it from touching the water surface at any time.

Questions about your situation and what type of device might be required? Please contact Metro Water Services at 615-862-4600.

Safe Practices For Everyone

We all rely on each other to keep dirt & bacteria, herbicides & pesticides, soaps and other contaminants out of our drinking water supply. A cross-connection exists when possibly contaminated water could enter the drinking water system. Backflow can occur anytime. All that is needed is water pressure drop in the water main, most commonly caused by fire fighting or a water main break. When that happens, contaminated water from your garden hose could flow backwards – through your house and into our community’s drinking water system.
You can help by using these simple methods to keep our drinking water safe

Keep Your Garden Hose Safe

Keep dirt & bacteria, herbicides & pesticides, soaps and Graphic: faucet, hose, sprayer, flower Text: Hose bibb vacuum breakerother contaminants out of your water supply.

Always install a hose bibb vacuum breaker (HBVB) on the outside faucet. This inexpensive backflow prevention device ($4-10) is available from your local hardware store. It makes sure that no harmful materials are drawn back into the drinking water system through your hose.  Every outdoor faucet should be protected with a HBVB to keep herbicides, pesticides, and even dirt out of the water system.

Never immerse a hose in a bucket, pond, pet water dish, or the fish tank. Bacteria and chemicals can be drawn into water meant for your family. If someone drinks or bathes in contaminated water, it can cause serious health problems or death.

Why? … Because a change in water pressure could pull water from your hose into your house and into the drinking water system. Water pressure changes occur on a regular basis - when hydrants are opened to fight fires and when water mains are being repaired.

Prevent Hose Immersion

Graphic: skull, cross bones, hose, faucet, xNever immerse a hose in a swimming pool bucket, pond, pet water dish, or the fish tank. Bacteria and chemicals can be drawn into water meant for your family. If someone drinks or bathes in contaminated water, it can cause serious health problems or death.

We can all do our part to keep our drinking water clean by avoiding cross connections and preventing backflow!