Water use in the United States reached its lowest level in 2015 in at least four decades. National trends, however, mask local challenges throughout the U.S. In some places, decreases in surface water use were more than offset by increases in groundwater use, leading to net increases in total withdrawals. Other places have seen increasing rates of water shortages caused by mixes of socioeconomic and climate forces. This study examines recent trends in freshwater use and makes projections in future freshwater use over the next 50 years. Projections are based on socioeconomic and climate scenarios from the Intergovernmental Panel on Climate Change Fifth Assessment Report. Scenarios are paired with five climate models from the downscaled Multivariate Adaptive Constructed Analogs (MACA). We find total consumptive water use will decrease by as much as 8% under the best‐case scenario but increase by as much as 235% under the worst‐case scenario. Results depend on both climate and socioeconomic changes, but because agriculture is the dominant use of water in most regions, climate change impacts overwhelm all other factors under hot and dry futures. For the wetter climate models, water use decreases even under the highest emissions levels and highest population growth rates.

Colorado’s water supply is under threat due to climate change pressures and population growth, however Colorado has been recognized to have some of the most progressive water conservation programs in the country. Limiting outdoor water consumption is an increasingly popular approach to conserving water in semi-arid cities, yet in order to implement effective water reduction and conservation policies, more utilities and city managers need a firm understanding of the local drivers of outdoor water consumption. This research explores the drivers of outdoor water consumption in a semi-arid, medium-sized Colorado city that is projected to undergo significant population growth. We used a combination of correlation and linear regression analyses to identify the key descriptive variables that predict greater water consumption at the household scale. Some results were specific to the development patterns of this medium-sized city, where outdoor water use increased 7% for each additional mile (1.6 km) a household was located from the historic urban center. Similarly, more expensive homes used more water as well. Surprisingly, households with a higher ratio of vegetation cover to parcel size tended toward less water consumption. This result could be because parcels that are shaded by their tree canopy require less irrigation. We discuss these results to assist city managers and policymakers in creating water-efficient landscapes and provide information that can be leveraged to increase awareness for water conservation in a growing, semi-arid city.

Research has shown that urban tree canopy (UTC) provides a multitude of ecosystem services to people in cities, yet the benefits and costs of trees are not always equitably distributed among residents and households. To support urban forest managers and sustainability planning, many studies have analyzed the relationships between UTC and various morphological and social variables. Most of these studies, however, focus on large cities like Baltimore, MD, Los Angeles, CA, and New York, NY. Yet, small and midsized cities are experiencing the most growth globally, often having more opportunity to alter management strategies and policies to conserve and/or increase canopy cover and other green infrastructure. Using both a linear and spatial regression approach, we analyzed the main drivers of UTC across census block groups in Fort Collins, CO, a midsize, semi-arid city projected to undergo significant population growth in the next 20-30 years. Results from Fort Collins indicated that block groups with older buildings and greater housing density contained more UTC, with 2.2% more canopy cover for every 10 years of building age and 4.1% more for every 10 houses per hectare. We also found that distributional inequities may already be developing within this midsized city, as block groups with more minority communities were associated with lower UTC. We compared the drivers of UTC in Fort Collins to other cities located in different climate regions, or biomes, and in various stages of urban development. Based on these results, we suggested future urban forest management strategies for semi-arid cities like Fort Collins.

This archive contains research data collected and/or funded by Forest Service Research and Development (FS R&D), U.S. Department of Agriculture. It is a resource for accessing both short and long-term FS R&D research data, which includes Experimental Forest and Range data. It is a way to both preserve and share the quality science of our researchers.