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Water Waste Adds Up

Most of us don't think much about the dripping faucet, leaky hose, running toilet or swampy sprinkler head we may live with for months. But those continuous forms of water waste add up faster than you might think. The tables below illustrate how a tiny leak can turn into a big water bill.

The following table uses the same calculations to estimate the consumption with common household measurements.

Water Waste Adds Up: Common Measures
If a leak as a continuous flow of: It wastes the following number of gallons in:
  1 Hour 1 Day 1 Year
1 cup (1/16 gal) per minute 4 90 32,850
1 pint (1/8 gal) per minute 8 180 65,700
1 quart (1/4 gal) per minute 15 360 131,400
2 liters (about 1/2 gal) per minute 32 761 277,698
1 gallon per minute 60 1,440 525,600

A leak measured in cups is an obvious problem that few of us would ignore. A dripping faucet is harder to measure and easier to let go “for now.” As “for now” stretches to weeks, the water waste adds up, often much faster than we imagine.

The amount of water dripping slowly from a faucet is difficult to measure. Not only do drop sizes vary, but terms like “slow drip” vary from person to person. Still, as long as a faucet is leaking, it’s wasting water. And that waste will add up. If all of Denver Water’s single-family residential households found and fixed a one-drip-per-second leak, they would save about 82 million gallons a year.

Water Waste Adds Up: Drips Turn Into Gallons
If a leak has a continuous flow of: It wastes the following number of gallons in:
  1 Day 1 Year
5 drips in 30 seconds 1 347
10 drips in 30 seconds 1.9 694
15 drips in 30 seconds 2.9 1,041
20 drips in 30 seconds 3.8 1,389
25 drips in 30 seconds 4.8 1,736
30 drips in 30 seconds 5.7 2,083
35 drips in 30 seconds 6.7 2,430
40 drips in 30 seconds 7.6 2,777
45 drips in 30 seconds 8.6 3,124
50 drips in 30 seconds 9.5 3,472
55 drips in 30 seconds 10.5 3,819
60 drips in 30 seconds 11.4 4,166

Toilet leaks add up, too

A leaking toilet pouring water down its outflow tube can easily waste 100 to 250 gallons per day. A stream of water the thickness of a pencil, from a faucet or sprinkler head, filling a cup in 30 seconds equals 1 pint per minute and more than 65,000 gallons per year. Denver Water's usage table, "Where Your Water Goes," shows consumption averages for household use.

Landscape efficiently to prevent waste

Landscape irrigation typically uses at least half of a household’s total consumption. Kentucky bluegrass, a common type of turf used for lawns in Colorado, will use about 1.5 inches of water in the heat of the summer. Less water use is required in the cooler spring and fall seasons. One gallon of water will cover a one square-foot area of lawn 1.5 inches deep. For the irrigation season, up to 18 gallons per square foot of lawn is required to supplement natural precipitation. As natural precipitation increases, supplemental irrigation demand decreases. Hence, a 50- by 50-foot lawn will require approximately 45,000 gallons per irrigation season (six months).

Seeding your lawn with native grasses can cut this consumption in half, and planting low-water-use plants can make a big impact in your outdoor water usage too.