A California Department of Water Resources (DWR) geologist measures and records a pumping water level in a production well. Photo by John Chacon,/DWR, 2013

Jay Lund, Thomas Harter, Robert Gailey, Graham Fogg, Richard Frank, Helen Dahlke, Timothy Ginn, Sam Sandoval Solis, Thomas Young — UC Davis
Andrew Fisher, Ruth Langridge — UC Santa Cruz
Joshua Viers, Thomas Harmon — UC Merced
Patricia Holden, Arturo Keller — UC Santa Barbara
Michael Kiparsky — UC Berkeley
Todd Greene, Steffen Mehl — California State University, Chico
Jason Gurdak — San Francisco State University
Steven Gorelick, Rosemary Knight — Stanford University

California is entering a new era in how it manages its largest source of water storage — groundwater. Initial efforts implementing the state’s new Sustainable Groundwater Management Act must focus on getting local and state agencies organized and able to communicate with each other. Having common expectations for the contents of the law’s required “Groundwater Sustainability Plans” will save the agencies and stakeholders considerable grief and confusion. Here is how the contents of the local plans might be organized to support both local and statewide objectives for groundwater sustainability.

Groundwater plans

The new law, which took effect Jan. 1, broadly defines “sustainability” as avoiding “undesirable results,” [Section 10721 (u)-(w)] in terms of groundwater overdraft, land subsidence, water quality degradation, seawater intrusion and groundwater-surface water interaction. The local sustainability plans are not required to address undesirable results that occurred before Jan. 1 [Section 10727.2 b (4)].

The law requires regional agencies to prepare the Groundwater Sustainability Plans for groundwater basins that the California Department of Water Resources has designated “high” and “medium” priority. The department has preliminarily assigned these designations to 127 of the state’s 515 basins [1].

The law provides a framework for the plans (Section 10727) but refrains from a prescriptive state role. It requires the department to create technical criteria and regulations by which it will evaluate the appropriateness of the local plans and their implementation (Section 10733). The department must adopt the regulations before June 1, 2016. The design of these regulations and their technical and scientific requirements will be critical to the success of the plans.

In the coming months, there will be much discussion on the content of these rules among department staff and advisors and in public meetings. The initial 2016 regulations will likely be refined over time [Section 10733.2 b (1)], but all parties have an interest in a well-designed initial regulatory framework to guide the development and evaluation of the local sustainability plans.

Making the local plans effective

To be effective, the plans must be based on the physical realities of geology, hydrology and land use. Groundwater balances are central. However, groundwater sustainability might not simply balance basin pumping with natural recharge; under natural conditions inflow is balanced by natural outflow to streams and groundwater-dependent ecosystems. Today, additional stream depletion and deep percolation of irrigation water increase total basin inflows.

Delivery point of the Coachella Valley Water District’s groundwater replenishment facility. Photo by Kelly M. Grow/California Department of Water Resources

Plans also should be realistic on local, economic, political and legal conditions, including logistics in implementation and relationships to neighboring plans and finances. The plans also must clarify the responsibilities and authorities of local agencies for implementation, and specify contingencies for when conditions deviate from plan assumptions or projections (including surface water deliveries and inflows from other basins).

“Groundwater Sustainability Agencies” responsible for developing basin plans will need to make controversial decisions. The state regulations should require transparent development of sustainability objectives and analysis to inform decision-makers, regulators and courts. The technical information should include:

• Local concerns, objectives and definition of “sustainability”
• Water balances for the basin under present and potential future conditions
• Data collection and reporting to inform, monitor and evaluate analyses and plans
• Overall assessment of groundwater basins
• Management alternatives available to achieve local sustainability objectives

U.S. Geological Survey scientists say cracks and buckles along the Delta-Mendota Canal are likely caused by subsidence from groundwater overdraft. Photo by Amy Quinton, Capital Public Radio, November. 2013 

Each major management alternative should be technically assessed on its likelihood of success as well as its cost (including delayed costs and those to third parties) and performance — physical, economic, social and environmental. Science-based planning and management requires that contingencies be flexible enough to accommodate major unavoidable uncertainties.

Clear and timely communication among stakeholders will be critical to reduce conflict and build creative solutions with broad local support. This requires:

• Data organization, transparency and availability
• Sharing knowledge, concepts, management options and assessment of desirable and undesirable outcomes
• Examination of uncertainties in knowledge, data and predictability of outcomes
• Clear analytical comparison and discussion of alternatives leading to a preferred plan

Crafting the Groundwater Sustainability Plans so they can be effective on (and under) the ground and fairly evaluated by state regulators and courts is an immense technical and institutional challenge. Thoughtful state regulations on the development and contents of these plans will be essential.

A proposed table of contents

Here we propose a preliminary table of contents for a typical Groundwater Sustainability Plan. More details and structure are suggested in an outline that can be downloaded here. This outline includes technical items we believe are needed for effective plans. Tiers of content depend on basin complexity. Additional items might also be useful, and some items might not be needed for simpler cases.

A Table of Contents
for
Groundwater Sustainability Plans  

1. Summary statement of local basin sustainability objectives and approaches
2. Basin geography and GSP organization: description of basin, water sources and uses; Summary of major basin problems related to groundwater; organization of local Groundwater Sustainability Agencies; defining roles and authorities relative to other local and regional agencies
3. Summary of basin hydrogeology: geologic context of local groundwater; major water flows in and out of basin; changes in storage with time; variability in flows and storage; how flows are likely to change with climate, population, and land use; susceptibility to land subsidence, saltwater intrusion, loss of habitat and other problems related to groundwater use
4. Sustainability objectives, options and analysis: basin-specific definition and objectives for sustainability (quantity, quality, land subsidence and groundwater/surface water interaction); options and effectiveness for achieving sustainability; groundwater deliveries for different water budget management options, including uncertainties
5. GSP activities: management activities; implementation responsibilities and enforcement; timelines, funding, measurement and verification; agreements with neighboring and regional basins, water suppliers and land-use authorities on water management and supply and information sharing; strategies for moving forward in the absence of ideal data, including additional near-term data gathering; monitoring plans; recourse contingencies for changes in surface water availability, to make implementation more robust; monitoring plans
6. Implementation actions supporting GSP activities: near-term actions and responsibilities; efforts and responsibilities for improving information and reducing uncertainties to manageable levels; efforts to assess achievement of plan objectives

Technical appendices:

1. Basin hydrogeology
2. Details of water budget component calculations
3. Water quality, including natural and anthropogenic sources of contamination
4. Options considered for achieving sustainable management
5. Process of GSP development, including local and stakeholder engagement and analysis
6. Details of monitoring and assessment plans
7. Other supporting documents

PDF file of table of contents
PDF file of more detailed table of contents

[1] Links to further information on the Sustainable Groundwater Management Act of 2014:

• The act
• Initial groundwater basin prioritization
• Prioritization results
• Basin prioritization map