Source: California Department of Water Resources

by Thomas Harter, Vicki Kretsinger Grabert, Reid Bryson, and Tim Parker

On May 26, 2016, eight days after the California Water Commission voted to approve emergency regulations for Groundwater Sustainability Plans, the Groundwater Resources Association (GRA) held the sixth annual workshop of the Contemporary Groundwater Issues Council (CGIC) to address a closely related component of Sustainable Groundwater

Cover for the Ground Water Sustainability Plan (GSP) Annotated Outline. Source: California Department of Water Resources

Management Act (SGMA) implementation: best management practices (BMPs).  With input from CGIC and other groups, the Department of Water Resources (DWR) has since
published its first round of BMPs and Guidelines on some core activities within Groundwater Sustainability Plans (GSPs): monitoring protocols, monitoring networks, development of hydrogeologic conceptual models, water budgets, and modeling. Additional BMPs and guidelines as well as statewide data support will be forthcoming as Groundwater Sustainability Agencies (GSAs) prepare their GSPs. Guidance on establishing sustainable management criteria, on engaging with tribal governments, and on communication and stakeholder engagements are next on DWR’s list.

The CGIC brainstormed around several areas related to BMPs and key actions by GSAs. The workshop results identified some key short-term and long-term GSA activities that would need support by the state. Short-term actions included the need for organization and communication at the local level to create or strengthen the foundation for future groundwater management decision-making.

Suggestions for short-term actions included:

• building trust amongst local agencies, stakeholders, and the public through clear communication about the goals of sustainable groundwater management and governance options;
• targeted capacity-building to encourage participation by all stakeholders; and
• coordination of current monitoring and modeling efforts within a basin or subbasin.

Suggestions for long-term actions included:

• investing in monitoring programs to fill data gaps,
• developing projects to enhance recharge (particularly in areas subject to overdraft and areas where hardpans or other physical constraints limit natural recharge), and
• developing a systematic approach to the evaluation and revision of water budgets to improve their accuracy.

Source: California Department of Water Resources

The BMPs since developed by DWR provide support for some of these important GSA
activities. Some ideas, considerations, and stated challenges around BMPs remain open and will continue to be discussed as GSAs, DWR, and the State Water Board move toward developing their GSPs. BMPs that the CGIC had also considered critical (but that did not make DWR’s initial round of publications) included governance, financing (both short-term and long-term), and (local) data-management systems.

Other, perhaps less urgent but important, state guidelines that the CGIC suggested that the state develop, included:

• BMPs or guidances on water markets, groundwater-recharge rebates, and water-management approaches ranging from centralized decision-making to market-based allocations;
• understanding and responding to uncertainty in water budgets,
• process guidance for avoiding minimum thresholds and triggers, and
• developing recharge programs (particularly those that encourage distributed recharge where a GSA or local agency may not be able to meter the amount of recharge, but which can nonetheless be significant on a regional scale).

Source: California Department of Water Resources

One area of particular concern included activities around the management of groundwater dependent ecosystems (GDEs) and surface water flows impacted by groundwater management. Many GSAs and local agencies will face challenges managing this important aspect of sustainability.  Some of those challenges stem from a lack of clarity in SGMA regarding the responsibility to manage groundwater basins to avoid impacts on GDEs, as compared to significant and unreasonable depletions of surface water.

Several participants noted that GSAs will need clear communication from DWR and the State Water Board as to the various datasets that the state will provide to GSAs versus those datasets that GSAs should anticipate developing at the local level.  Participants also noted that local agencies will need guidance from the state regarding its interpretation of requirements under SGMA for local agencies to:  (1) identify and map GDEs, and (2) avoid impacts to GDEs, relative to efforts associated with other interactions of surface water and groundwater, including non-ecosystem-related beneficial uses.  Urgency was placed at finding funding for additional surface water and groundwater monitoring to assess interconnected resources that may be implemented by the state and/or local agencies.

The CGIC suggested that DWR consider developing BMPs and guidance around several topics related to groundwater-surface water interaction:

• monitoring surface-water/groundwater interactions at spatial and temporal scales relevant to basin management;
• methods for modeling or otherwise quantitatively evaluating surface-water/groundwater interactions, including accounting for impacts that may result from groundwater pumpage that occurred after January 1, 2015, but that will not result in immediate impacts to groundwater-connected surface waters;
• reservoir-management strategies for basins where reservoir releases have a significant impact on surface-water flow regimes; and
• adaptive-management approaches suited to avoiding significant impacts to surface waters.

Thomas Harter is a groundwater expert at the University of California, Davis. Vicki Kretsinger Grabert (President and Senior Principal Hydrologist) and Reid Bryson are with Luhdhorff & Scalmanini, Consulting Engineers. Tim Parker is a consultant.

Further Reading

Sustainable Groundwater Management Act. CA Department of Water Resources

Groundwater Sustainability Plan Emergency Regulations (GSP Regulations). CA Department of Water Resources

BMP Framework Document. CA Department of Water Resources

BMP 1: Monitoring Protocols, Standards, and Sites. CA Department of Water Resources

BMP 2: Monitoring Networks and Identification of Data Gaps. CA Department of Water Resources

BMP 3: Hydrogeologic Conceptual Model. CA Department of Water Resources

BMP 4: Water Budget. CA Department of Water Resources

BMP 5: Modeling. CA Department of Water Resources

Preparation Checklist for GSP Submittal. CA Department of Water Resources

GSP Annotated Outline. CA Department of Water Resources