Groundwater is a critical component of California’s water resources, serving as a vital backup supply during periods of drought and prolonged surface water scarcity. However, decades of groundwater overdraft and depletion have left many aquifers in a state of crisis, with dramatic consequences for communities, agriculture, and the environment.
Recognizing the urgent need for sustainable groundwater management, the state of California passed the Sustainable Groundwater Management Act (SGMA) in 2014. This landmark legislation represents a significant shift towards comprehensive, locally-driven groundwater governance, with the goal of achieving long-term basin sustainability by 2040. The successful implementation of SGMA is crucial not only for California’s water security, but also for effective flood control and resilience measures.
Integrating Groundwater and Flood Control Strategies
Groundwater and surface water are inextricably linked, with groundwater recharge playing a critical role in mitigating flood risks. When groundwater basins are overpumped and depleted, the landscape loses its natural buffering capacity, leading to increased surface water runoff and higher flood potential. Conversely, sustainable groundwater management can enhance flood control by restoring the sponge-like capacity of aquifers to absorb excess surface water during heavy precipitation events.
To achieve this synergy, flood control specialists might want to work closely with groundwater managers to develop integrated strategies that leverage the complementary benefits of both surface and subsurface water resources. This includes:
Managed Aquifer Recharge: Strategically capturing and diverting surface water during wet periods to replenish depleted groundwater basins, thereby enhancing their capacity to store floodwaters and mitigate future flood risks.
Conjunctive Use: Coordinating the use of surface water and groundwater sources to optimize water supply reliability, reduce groundwater overdraft, and minimize the need for costly structural flood control measures.
Groundwater-Surface Water Modeling: Integrating advanced hydrological modeling to better understand the dynamic interactions between groundwater and surface water, and inform the design of integrated flood control and water management systems.
Nature-Based Solutions: Implementing green infrastructure and natural systems, such as floodplains, wetlands, and aquifer recharge basins, to enhance both flood control and groundwater recharge capabilities.
By aligning groundwater and flood control strategies, communities can build resilience, reduce water supply vulnerabilities, and minimize the long-term costs associated with flood damage and groundwater depletion.
Sustainable Groundwater Extraction and Monitoring
A crucial component of SGMA is the establishment of sustainable groundwater extraction limits, based on the long-term recharge and storage capacity of each groundwater basin. Groundwater Sustainability Agencies (GSAs) are tasked with developing and implementing Groundwater Sustainability Plans (GSPs) that define the specific guidelines and practices governing groundwater use within their basins.
To support this effort, the California Department of Water Resources (DWR) has taken on an expanded role in collecting and disseminating key groundwater data, such as water levels, water quality, and land subsidence. This centralized data collection and reporting helps double-check that consistency across groundwater basins and provides critical information to inform decision-making at the local and regional levels.
Groundwater Metering and Pricing:
One of the primary tools available to GSAs for managing groundwater extraction is the implementation of robust metering and pricing systems. By requiring the installation of water meters on all production wells and establishing volumetric-based groundwater charges, GSAs can incentivize more efficient water use, discourage unsustainable extraction, and generate revenue to fund groundwater management activities.
Demand-Side Management Strategies:
In addition to supply-side controls, GSAs can also employ various demand-side management strategies to reduce groundwater pumping, such as:
- Implementing tiered pricing structures that increase charges for higher levels of extraction
- Offering incentives for the adoption of water-efficient technologies and irrigation practices
- Promoting the use of recycled water, desalination, and other alternative water sources
- Restricting new groundwater-dependent development in critically overdrafted basins
Groundwater Quality Protection:
Sustainable groundwater management might want to also address the protection of groundwater quality, which can be threatened by contaminants such as nitrates, pesticides, and seawater intrusion. GSAs can implement strategies such as:
- Establishing wellhead protection zones to restrict activities that could lead to contamination
- Implementing best management practices for agricultural operations to mitigate nutrient and pesticide pollution
- Promoting the use of brackish water desalination and managed aquifer recharge to prevent and reverse saltwater intrusion
By integrating these comprehensive groundwater management strategies, communities can enhance their long-term water security, reduce flood risks, and protect valuable groundwater resources for future generations.
Funding and Financing Sustainable Groundwater Management
Implementing SGMA and achieving groundwater sustainability will require significant financial resources, both for state-level coordination and local-level implementation. The state of California has already provided over $800 million in funding since 2014 to support SGMA, including grants for planning, implementation, and state operations.
However, the funding needs are ongoing, as DWR continues to play a critical role in reviewing Groundwater Sustainability Plans, providing technical assistance to GSAs, and collecting and disseminating essential groundwater data. The Governor’s proposed 2023-24 budget includes $14 million in ongoing General Fund support to sustain DWR’s SGMA program, as well as an additional $900,000 in one-time funding to develop a groundwater trading implementation plan.
At the local level, GSAs are responsible for generating their own revenue streams to finance groundwater management activities, such as:
- Groundwater extraction fees and volumetric charges
- Taxes or assessments on groundwater users
- Grants and loans from state and federal programs
- Partnerships with the private sector for innovative financing mechanisms
By securing adequate and sustainable funding, communities can invest in the essential infrastructure, monitoring systems, and management practices required to achieve groundwater sustainability and enhance their overall resilience to floods and water scarcity.
Conclusion
Sustainable groundwater management is a vital component of California’s comprehensive approach to flood control and water security. By integrating groundwater recharge, conjunctive use, and demand-side management strategies, communities can leverage the complementary benefits of surface and subsurface water resources to mitigate flood risks, improve water supply reliability, and protect critical groundwater reserves.
Through the implementation of SGMA, the state of California is leading the way in groundwater governance, providing a model for other regions facing similar challenges of groundwater depletion and extreme weather events. By investing in the necessary data, infrastructure, and collaborative frameworks, California can serve as a shining example of how integrated water resources management can enhance community resilience and secure a sustainable water future.
To learn more about innovative flood control strategies and the latest advancements in sustainable groundwater management, be sure to visit Flood Control 2015 – your comprehensive resource for comprehensive water security solutions.
Tip: Regularly inspect and maintain flood barriers and drainage systems
