Colorado Water Conservationists New Target: Nonfunctional Turf
Governor Polis signed Senate Bill 24-005 into law on March 15th, 2024, which prohibits landscaping practices for water conservation. The bill prohibits nonfunctional turf, artificial turf, and invasive plant species from being planted on applicable property. The applicable property includes commercial property, common interest community property, street right-of-ways, parking lots, medians, and transportation corridors. The bill articulates five exceptions, including allowing ornamental turf that is a native plant or has been hybridized for arid conditions. The bill doesn’t impact individual homeowners or places that have “functional turf” which is used for human recreation and includes playgrounds, amphitheaters, golf courses, picnic grounds and sports fields. The bill goes into effect January 1, 2025 and is not retroactive, meaning it only applies to new constructions and projects.
The problem with turf grass is that it requires large volumes of water to keep alive. This is especially true in Colorado’s dry climate where there is limited precipitation to water lawns, and homeowners must rely on potable water for irrigation. Denver Water estimates that watering lawns accounts for fifty percent of a single family home’s water use. In addition, the EPA estimates that as much as 50 percent of water used for irrigation is wasted due to evaporation, wind, or runoff. Non-native turf grass has very shallow root structures which result in more water draining from the grass and into sewers than being used for its growth. Native grasses, on the other hand, evolved in Colorado’s dry arid climate and developed incredibly long root structures to reach water that has percolated into the soil. This allows water to percolate into the ground instead of running off and being wasted. Native grasses also evolved to use up to 90% less water than non-native turf grasses.
Native plants in landscapes also provide ecosystem services other than just conserving water; they increase biodiversity, reduce heat island effect, sequester carbon, and reduce air pollution. Native plants attract a multitude of other species and create vital habitat for native birds and pollinators which are vital to the ecosystem. The flat, dark surfaces of turf lawns absorb heat and actually raise urban temperatures, which has been termed “urban heat island effect”. Having a landscape which incorporates trees and other native plants can help lower temperatures and fight this effect. Additionally, shrubs and native plants are larger and have longer root systems which store more carbon than short grass. Because of this, native plants filter more air than a lawn can and greatly reduce air pollution.
Water is a scarce and valuable resource in Colorado and climate change will make the situation more severe. The bill states that water conservation is “a matter of statewide concern” and “in the public interest”. The benefits of limiting non-native and nonfunctional turf grass goes farther than water conservation, and the bill states that they “can be replaced with landscaping that adheres to water-wise landscaping principles without adversely impacting quality of life or landscape functionality.” This bill is another crucial step for Colorado to continue addressing its water crises by increasing the benefits of using alternative native plantings in urban landscapes. Now it is also up to urban homeowners to do their part to limit nonfunctional turf and replace it with native options, and to reap the ecosystem benefits of a native yard!