Modern hydrologic modeling and data systems are growing in scale and resolution to answer urgent, data intensive questions related to water resources. The focus of this dissertation is how real-world entities can be represented as flexible and efficient computational elements that capture processes and ease the exchange of information. Part 1 focuses on evaluating the state-of-the-art National Water Model (NWM) and Height Above Nearest Drainage flood mapping techniques to establish a community benchmark for improvement. We propose a outline for what an intelligent emergency response system might look like with these systems in place but note challenges related to (1) data usability (2) assumptions of spatial homogeneity in explicitly heterogeneous phenomena, and (3) the application of historical conventions that are inefficient in a federated system.

Part 2 focuses on (1) improving the data format of NWM streamflow output (2) parameterizing Manning’s roughness across the national river network for improved river depth estimates, and (3) the digital representation and estimation of hydraulic relations at the national scale for increased interoperability. Part 3 utilizes these techniques to reimagine a flood forecasting system that circumvents the need to produce flood maps and instead computes feature-level flood forecasts through a relational data system that allows building-level and demographic flood assessments to be extracted from a national inventory in a matter of seconds for any area of interest.

Lastly, part 4 explores the role of land cover as the mediating layer of human, water, and energy processes. The questions explored include how land cover data is best represented at coarser scales and what are the hydrologic consequences of variable spatial allocation and static land cover data. In approaching these, we develop a new raster resampling technique, evaluate the hydrologic influence of fire over California in the last two decades, and quantify the sensitivity of hydrologic models to different land cover representations. The dissertation concludes by sharing a simulation of California land use change out to 2100 and a discussion of the potential impacts faced.