Achieving Groundwater Sustainability is Hard

GRAT makes it easier

The Groundwater Recharge Assessment Tool – GRAT gives agricultural water providers and Groundwater Sustainability Agencies (GSAs), essential insights to maximize groundwater recharge opportunities.

GRAT’s cloud-based application integrates hydrologic, agronomic and geologic science with best-available data from local, state and federal sources to create an indexed ranking of suitable recharge sites.

As a planning tool, GRAT enables districts and GSAs to more efficiently create, evaluate and implement Groundwater Sustainability Plans (GSPs). As an operations tool, GRAT helps districts avoid missed opportunities to augment their water supplies by optimizing district recharge.

With guidance from existing partners and our Technical Advisory Committee, we continue to enhance GRAT capabilities.

What Users are Saying About GRAT

“GRAT is a great resource for districts and GSAs like mine throughout the Valley that can benefit from utilizing water for on-farm groundwater recharge. Knowing where and when to do recharge is critical, and GRAT provides the insight.” Don Cameron, Vice President and General Manager of Terranova Ranch
“GRAT is an optimization tool that we will use to identify the low hanging fruit related to basic recharge practices — dedicated basins, fallowed ground, production farmland and in-lieu. It will help identify the most cost-effective actions to improve our recharge opportunities.” Eric Averett, General Manager, Rosedale-Rio Bravo Water Storage District
“TID sees GRAT as an integral tool to employ with Groundwater Sustainability Planning to identify project and management actions. TID will also use it on a real-time basis in future years to direct surplus flows for optimum recharge.” Paul Hendrix, former Tulare Irrigation District General Manager

Augment Your Water Supply

Put your data and science to work with GRAT

Take the guesswork out of optimizing recharge by easily answering hard questions such as:

  • Where and when is recharge best done?
  • How much surface water can we capture?
  • How much of our groundwater overdraft can be addressed by increasing recharge?

GRAT helps districts and GSAs quickly identify:

  • Where the most cost-effective on-farm recharge options are
  • When those options exist by week, over a 20-year horizon, with multiple rain-year types
  • How much water might be recharged
  • Environmental and social implications of recharge options in your basin

GRAT’s nearly unlimited scenarios and customized reports, comparing recharge methods, water recharged, and cost-effectiveness of each practice, inform successful recharge operations, financing, implementation, and stakeholder engagement.

How Does GRAT Work?


GRAT was developed by Sustainable Conservation and The Earth Genome in conjunction with irrigation districts, growers and agronomists. It integrates hydrologic, agronomic and geologic science with the best available data from local, state and federal sources.

Screenshot of GRAT tool crop selection
Explore recharge options in your district with the easy map-based interface.
Screenshot of GRAT tool sliders
Evaluate and prioritize thousands of potential recharge locations.
Screenshot of GRAT tool parameter settings
Run and save scenarios in minutes.
Screenshot of GRAT tool with dynamic report settings
See dynamic results reports and 20+ additional data overlays (show CASGEM groundwater levels).


Our Suite of GRAT Partnership Services

Sustainable Conservation and Earth Genome, both non-profit organizations, developed GRAT with the support of local agency and foundation funding.

Sustainable Conservation has been working with farmers and irrigation districts since 2011 on affordable, practical ways to capture floodwater on farmland.

We are seeking new partnerships with GSAs — partnerships that will allow you to apply GRAT in your local areas and successfully evaluate options for achieving Sustainable Groundwater Management Act (SGMA) goals. GRAT is ready to be applied in Central Valley locations where surface water can be diverted and distributed to potential recharge sites through canals and pipelines.

Our services to partners include:

  • Localization Setting up GRAT for your district and GSA
  • Data Processing, importing, & updating
  • Defaults WAFR scenario support & defining tool defaults
  • Training and Support In-person GRAT training and support (initial and ongoing)
  • GSP Support Coordinating GRAT with consultants/constituents
  • Reporting Minor customization of graphs/results on request

We are seeking new partnerships with agricultural water providers and GSAs – partnerships that make augmenting water supply and achieving Sustainable Groundwater Management Act (SGMA) goals easier.

We anticipate a 2-4-month implementation timeline for each new GRAT partnership, depending on availability of local data and conveyance-system complexity.

Groundwater Recharge in the Media

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