New Mexicos Dynamic Statewide Water Budget (NMDSWB) NMDSWB Project - PowerPoint PPT Presentation

New Mexico’s Dynamic Statewide Water Budget (NMDSWB)

NMDSWB Project Goals • Provide a water accounting process for the State of New Mexico – Where the water is – How water is used and where it goes – Identify gaps in knowledge about water in New Mexico • Present regional and statewide water data in a comprehensive and consistent visualization platform • Estimate future water supply and demand through scenarios • Connect science to decision makers and stakeholder

NMDSWB Spatial Scales • 7 Major River Basins (black Lines) • 16 Water Planning Regions (colored areas) • 33 Counties (thin grey lines)

NMDSWB Mass Balance 1. Land Surface- Conceptual representation of soil moisture. The storage in this stock is currently not estimated and changes in storage are assumed to be zero Storages 2. Surface Water- Water flowing in rivers and other natural water ways that can be diverted or impounded for human use. No change in storage through time. At each timestep, the fluxes into and out of this stock are balanced. 1 3. Human Storage and Distribution Land Surface Systems- Water at any given time residing in manmade 2 Surface Water storage impoundments or distribution systems, such as public water supplies, irrigation canals, and reservoirs. When water is added to storage in a reservoir, it is considered a diversion of available surface water to the human storage system, and when it is released from storage, it is considered 3 Human Storage and a return to the available surface water system. Distribution Systems 4. Groundwater- Total groundwater storage is largely unknown except for select aquifers throughout the state. Currently the DSWB does not estimate groundwater storage, but it does track changes in storage over the selected time of 4 Groundwater a model run.

NMDSWB Mass 1. Precipitation - Monthly PRSIM data Balance Fluxes aggregated for given spatial scale 2. Runoff - Closure term to balance SW stock 3. Sw in /Sw out - USGS stream gage data 4. Gw in /Gw out - Presently unknown terms. Set Precip 6 to zero to allow for calculation of GW storage 8 9 5 ET SW2 ET h ET GW chage ET SW1 1 5. ET GW - Calculation based from USGS NLCD and Hargreaves reference ET estimate 2 Land Surface 6. Human use - Modeled/ data based human/diversions/consumption/ estimated 3 3 return flows Surface Water SW Out SW In 7. Recharge - Model assumes steady state GW SW d 6 system on all non-human terms. Recharge = SW r Recharge 6 baseflow + ET gw + GW out – GWin 8. Landsurface ET - Closure term to balance SW to GW 7 Human Storage and Land Surface. Landsurface ET = Precip – Recharge Distribution Systems - Runoff 9. ET SW - Calculation based ET sw2 + estimated GW r 6 ungaged SW return flows GW d 10 6 10. SW to GW - Closure term to balance Surface 4 Water System Groundwater GW Out 4 GW In

NMDSWB Future Scenarios 1. Climate Change Scenarios – Temperature, precipitation, surface water flows (GCM- data) 2. Human Population growth – Model impacts of growing demands for water in public and domestic water use sectors (High and low population growth forecasts) 3. Changes in water use and efficiency – Changes in on & off farm irrigation • efficiencies Per-capita water use rates • Commercial/industrial use • Power use and associated energy • use

Thank You https://nmwrri.nmsu.edu/new-mexico-dynamic-statewide-water-budget/ Ken.Peterson@tetratech.com