GRACast: Water Available for Replenishment Report and Estimates

Presented by:

James Wieking, California Department of Water Resources

 

 As part of the Sustainable Groundwater Management Act, the California Department of Water Resources (DWR) is directed to “prepare and publish a report by December 31, 2016, that presents the department’s best estimate, based on available information, of water available for replenishment of groundwater in the state.”

The notion of “Water Available for Replenishment of Groundwater” includes two constituent parts. The first part, “water available,” indicates a quantity of water that could be developed by one or more water available methods (surface water, conservation, recycled water, desalination, etc.) and matched to specific groundwater replenishment project(s). The second term, “for Replenishment of Groundwater,” designates the physical process of the augmentation of a groundwater basin, by natural or artificial means, including active recharge and in-lieu recharge. Consistent with this approach, DWR has developed planning guidance for both water available and for replenishment methods. Successful replenishment will likely require coordinated implementation of both a water available and a for replenishment project or management action.

The presentation will focus on the tools, methodologies, and assumptions DWR used to estimate “Water Available for Replenishment” for surface water. Two analytical approaches were synthesized to calculate outflow: 1) Gage Data Method and 2) Water Evaluation and Planning (WEAP) tool.   Conceptual and illustrative projects are then applied to the outflow with two fundamental controlling factors: 1) instream flow requirement and 2) project diversion capacity.  For purposes of these conceptual estimates, DWR has assumed that available water can be dedicated for replenishment (i.e., replenishment is not a constraining factor). This conceptual method provides a simple planning estimate of water available for replenishment (as distinctive from a water available project-specific analysis as required for a water right application). Groundwater Sustainability Agencies can use adaptations and refinements of the methods and approaches DWR has developed, or similar analytical approaches, to provide description and analyses for their agency, as a required element of their Groundwater Sustainability Plan.

 

*Early Registration (January 6) is $75 for Members* and $100 for Non-Members*
*Registration after January 6 is $100 for Members* and $125 for Non-Members*


SPEAKER BIO:

Jim Wieking is Supervising Engineer in the Statewide Infrastructure Investigations Branch, California Department of Water Resources and Project Manager of the Water Available For Replenishment team.  Jim specializes in water resources planning with emphasis in hydrology and operations.  Jim has experience in the State’s surface storage investigations, System Reoperation Program, and the California Water Plan.

 

MODERATOR BIO:

 

John Lambie, PE, PG, CWRE is a principal hydrogeologist with E-PUR, LLC, a water resource consultancy. John conducts water supply planning with an emphasis on groundwater and conjunctive water use options. He regularly applies his expertise in hydrogeologic modeling, wellfield exploration and design, and many other forms of quantitative analysis. John has experience in evaluating managed aquifer recharge options using surface waters to ensure water-supplies against quantity and quality risks.

 

Date: Jan. 11, 2017, noon - Jan. 11, 2017, 1 p.m.