Informing Efficient Landscape Watering through Weekly Neighborhood Watering Recommendations in College Station, Texas

Urban water utilities are increasingly grappling with the threat of drinking water scarcity amid intensifying extreme weather events and continued population growth. Despite decades of success in improving residential indoor water-use efficiency through low-flow water fixtures and appliances, outdoor water use may still represent up to 65% of total residential water use in many cities throughout the western United States and Texas. Up to half of water used outdoors is wasted because of inefficient sprinkler systems and overwatering. As cities in arid and semi-arid regions have sought to curtail outdoor water use amid multidecadal drought, many in humid climates have engaged with consumers to water their landscapes efficiently. Since 2015, the city of College Station, Texas, has implemented BVWaterSmart, a campaign for water conservation providing free weekly lawn watering recommendations to residents who subscribe. A network of eight rain gauges enables these recommendations to be furnished to households at the neighborhood level, capturing significant differences in irrigation requirements. Here, we examine the impact of this targeted behavioral intervention on outdoor water-use efficiency for nearly 300 single-family households using monthly water billing data and landscape water needs estimated using daily precipitation and evapotranspiration. Preliminary results suggest that irrigation efficiency improved for up to two years post-intervention, marked by a reduction in irrigation relative to the water budget and decreases in over-irrigation volume and frequency. Lessons gleaned from this study can help water utilities elsewhere implement a similar behavioral intervention program to promote water conservation through efficient use.