1. Underground Aquifers: California has vast underground aquifers, which can serve as natural reservoirs. Investing in aquifer storage and recharge infrastructure can help capture excess water during heavy rains and store it for drier times.

2. New Reservoirs: Construct new reservoirs and dams in strategic locations to store floodwaters. Consider environmentally friendly designs to minimize ecological impacts.

3. Off-River Reservoirs: These are reservoirs built away from rivers and streams, avoiding ecological disruption. They can store water pumped from rivers during high-flow periods.

Expanding Existing Infrastructure:

1. Raise Dam Heights: Increase the height of existing dams where feasible to increase storage capacity.

2. Offstream Reservoirs: Modify existing reservoirs to capture floodwaters and store them off-river.

Enhancing Natural Storage:

1. Wetlands and Floodplains: Protect and restore natural wetlands and floodplains to slow down water flow and increase absorption into the ground.

2. Reforestation: Plant trees in strategic areas to enhance water retention in watersheds.

Integrated Water Management:

1. Water-Use Efficiency: Implement measures to reduce water consumption, particularly during dry periods.

2. Recycled Water: Increase the use of recycled water for agriculture, industry, and landscaping.

3. Stormwater Capture: Design urban areas to capture and store stormwater for later use.

4. Interbasin Transfers: Develop infrastructure to move water from surplus regions to deficit regions.

Technology and Innovation:

1. Desalination: Invest in desalination technology to produce freshwater from seawater.

2. Cloud Seeding: Explore cloud-seeding techniques to potentially increase precipitation in certain areas.

3. Smart Irrigation: Implement agricultural technologies that optimize water usage and minimize waste.

Collaborative Efforts:

1. Public Awareness: Educate the public about the importance of water conservation and support for water infrastructure projects.

2. Interstate Cooperation: Coordinate with neighboring states to share water resources and manage water flows across basins.

3. Incentives and Regulations: Implement incentives and regulations to encourage water-saving practices and sustainable land-use policies.

By implementing a combination of these measures, California can mitigate the impacts of future droughts and improve overall water resilience in the state.