The Economics of Watering Your Lawn

The Economics of Watering Your Lawn

In January 2015, California Governor Jerry Brown declared a state of emergency due to California’s record-setting drought, requiring 25% in water savings across the state. Big agriculture is by far the largest consumer of California water, gulping up a whopping 77% of total use. Lawns are a factor too, however, and at 7% of total use residential lawns come in as the second largest consumer in the state.

Reducing water use on lawns presents an opportunity for both saving water, and in many cases, saving money. Many lawns in California, and across the United States, use grasses that are real water guzzlers, and governments and environmental advocates are urging transition to other types of greenery.

But exactly how much water is saved when these switches are made? And what are the costs of conversion? At Lawn Love we service tens of thousands of lawns, xeriscaped yards, and other water-smart alternatives, and we wanted to walk you through some of the economic implications here.

Generally, we found that if everyone in California got rid of their lawn it would save 5-7% of total water usage.  However, the financial payback to making such a change can take over 50 years to accrue, due in large part to the low cost of water.  So if you’re planning to ditch your lawn entirely, the payoff is largely environmental in nature.

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The future of the lawn is a controversial topic. Critics see lawns as extravagances that provide little value, and an obvious culprit of water overuse. Lawn reformists are generally proponents of converting yards over to hardscape, astroturf, or alternatives like cacti and other native plants.

Defenders of the lawn see it as unfairly under “Under Attack”, given that water use for lawns makes up a small fraction of total use. Many lawn proponents believe the lawn plays important roles culturally (recreation, beauty, etc.) and environmentally (oxygen, carbon sequestration, etc.). Rather than eliminate lawns entirely, they would prefer to see conservation through improved watering techniques and the use of drought-tolerant grass varieties.

Breakdown of California water use

california water use

Data: Centre for Landscape and Urban Horticulture

Americans consume water in a variety of manners: Showers, washing clothes, flushing toilets and, for many homeowners, watering lawns. The Water Utility of Sonoma reports that the average “three-person family in a single detached home uses about 150,000 gallons of water annually.” For families with lawns, this often represents the single largest use. A breakdown of this usage is below. These estimates are similar to other breakdowns of residential water use across the country.

Breakdown of household water use

water breakdown chart

Data: Water Utility of Sonoma County

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While there is a debate about how much emphasis should be put on conservation from lawns, even defenders of the lawn believe that there are a variety of ways water could be saved. A report from the University of California Cooperative Extension argues that improved irrigation and plant care practices (such as fixing leaks, optimizing the time of day for irrigation, and cutting grass at a greater height) can lead to significant water reductions.

Beyond just changing watering practices, many conservationists are proponents of replacing conventional lawn grasses with less water thirsty alternatives. There are a variety of options for those looking to transform their lawn: Switching to “low maintenance, drought resistant grasses,” introducing plant species like shrubs and trees, or using native plants can lead to greatly reduced water usage.

We used research from the University of California’s Center for Landscape and Urban Horticulture to estimate the gallons of water necessary in a given year for lawns with different types of plant species. These estimates are based on a 2,000 square foot lawn in the Sacramento Valley, and are probably on the low end of the average for a home in California. The formula used for these estimates can be found here. The estimates assume perfect distribution uniformity, which also may lead to underestimation.

Estimated total gallons of water per year by plant type: 2,000 sqft yard

gallons of water

Data: Centre for Landscape and Urban Horticulture

This data suggests a lawn made up of drought-tolerant grass can save as much as 25% on water use, and converting to native plants can save up to 60%.

For those that want to save the maximum amount of water and don’t want to have to deal with watering their yards, there are additional options.  One popular choice is xeriscaping, which is creating a landscape that minimizes applied water use (there is not necessarily an emphasis on native plants). Although it varies across regions, we found estimates suggesting it would cost around $5.50 per square foot to xeriscape a yard in California. This would come to $11,000 dollars for a 2,000 square foot yard.

Another option is to install artificial turf. We found it would cost an average of $10 per square foot to replace your existing lawn with artificial turf, which would come out to $20,000 for a 2,000 square foot lawn. Some consumers are concerned about the health and environmental effects of artificial lawns, but the government continues to promote their use.

Saving water also means saving on your water bill, but you have to be patient to see your investment repaid. Given that the costs to switch to a low water consumption may be over $10,000, and watering the same lawn would cost around $250 per year (at $.005 cents per gallon), it would take over 40 years for the investment to be repaid.

The Public Policy Institute of California studied the number of years it would take to recoup your investment from converting a lawn to a “water-efficient landscape” by region of California. Their estimates show that, for coastal Californians, it may take a lifetime for enough water savings to accrue that the investment pays for itself. For those in the California desert, the savings are more substantial. In a best case scenario, the conversion might pay for itself within a decade. The following chart displays the estimated number of years it would take to recover your investment in different areas of California (based on a midpoint of the Public Policy Institute’s scenarios):

Estimated years to recoup investment from lawn conversion

lawn investment chart

Data: Public Policy Institute of California

Based on these estimates, the average payback period is around 30 years for converting to a water-efficient landscape in California.

Given the long payoff of lawn conversion and the very immediate need to decrease water use, the California government has increased the incentive to convert to a low water use lawn. To entice people to convert their lawn, California and other states have introduced “cash-for-grass” subsidies that can add up to more than 5 dollars per square foot of lawn replaced with drought tolerant landscaping. The rebates are substantial enough that some companies will complete the conversion if the house owner hands over the rebate. The consumer gets the benefit of a lower water bill without having to pay for conversion, but one report suggests homeowners have had mixed reactions to losing their green garden.

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The expectation that a homeowner should keep a pristine, green lawn is a relatively recent idea, but it is deeply entrenched in our society. At least in California, the recent drought has challenged that expectation, and has forced Californians to think about the ways in which lawns might be changed to reduce water use. Drought-tolerant grasses, water-smart plants, and properly-functioning irrigation can go a long way in reducing overall water use, while still providing a beautiful, functional outdoor area.

Jeremy Yamaguchi