Artes: An Integrated Model of Water Supply in L.A. County

Los Angeles faces a future with less imported water. Infrastructure and institutions will have to adapt. Understanding emerging policy and investment needs requires analysis across systems, a typically elusive goal within the diverse and disparately managed water systems of L.A. A more comprehensive analysis of water resources in Los Angeles requires an understanding of people, pipes, and plants. It could also be flexible to incorporate the fast-changing landscape of models, data, and analysis that the active agencies of the region continue to develop.

With these goals in mind, we developed a water supply model for the metropolitan L.A. County region (Artes) to understand the potential for enhancing local water use across scenarios of demand and supply. The basic approach combines knowledge from engineering, hydrology, ecology, and sociology. The model is intentionally lightweight. Flexible and adaptive modeling can address many questions at multiple geographic scales, while also being able to incorporate new tools, data, and other models that are released. This model was developed to:

* Determine how local groundwater, recycling and stormwater capture supplies could maximally meet water demands across L.A. County, based on current knowledge of hydrology and hydrogeology

* Analyze tradeoffs in per capita water demand and available imported water supplies

* Investigate system-wide effects of increased conservation

* Minimize assumptions regarding data gaps

* Use modeling to highlight to key gaps in scientific understanding, while creatively addressing the shortfalls in a precautionary manner. For instance, we compare modeled and historic groundwater pumping and managed aquifer recharge to assess the potential for groundwater overdraft.

This manual describes important information for understanding model operations, assumptions, inputs, and outputs. The manual version (3.7) was written after development of 3 versions code for different research studies, which are in press or under review.