NSF Abstract

The Colorado River is facing its worst mega-drought in a millennium and is no longer able to meet the demands of the 40 million people in the United States who rely on it. As a result, cities throughout the U.S. Southwest are reconsidering both their dependence on imported water and the reliability and management of their existing 20th century water systems. In many cities in this region, the built, natural, and social systems conflict with advancing water conservation and sustainability. Faced with the pressures of climate change, population growth, and aging infrastructure, one possible strategy presents itself: reinventing community water management to thrive using only local water sources through a Net Zero Urban Water (NZUW) approach. NZUW is a holistic water planning approach that explicitly accounts for natural and human needs. This proposal focuses on Tucson, Arizona, where a net zero water ordinance is currently under development by the city and county and ambitious urban greening and tree canopy goals are key components of recently adopted city and county climate action plans. With increasing temperatures and urban heat island impacts, new water demands are emerging as cities move to expand their urban landscape to provide cooling benefits. Our community-identified research need explores how Southwest cities achieve NZUW balances while expanding urban greening and the associated socio-environmental co-benefits.

To conduct this research, our project fills local natural systems data gaps (Objective 1) and local social systems data gaps (Objective 2) to create an integrated NZUW evaluative tool (Objective 3) for urban greening goals. Local natural system data gaps will be met through a combination of in-situ data collection focused on quantifying vegetation water use and evapotranspiration via monitoring and discrete sampling (e.g., soil samples) across a set of Tucson urban landscape typologies. In Stage 1, these typologies and in-situ sites will be identified, and monitoring plans will be solidified with grant collaborators. Objective 2 will address social system data gaps through a series of workshops on public preference and key informant interviews with resource managers. In Stage 1, a work plan for the workshops and interviews will be co-created with civic partners and stakeholders. Finally, in Stage 1 a method will be solidified to use remote sensing data (NDVI, LiDAR, Orthophoto) and artificial intelligence to scale in-situ monitoring data across the city and county as inputs into the NZUW urban greening evaluative tool produced in Stage 2.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

Award Abstract #2432226