State agencies should automate data collection and reporting systems for critical water datasets, including groundwater elevation data, diversion data, and streamgage data
“A lack of water rights enforcement and lack of data on flow in some of these very remote areas makes it really difficult to establish targets to enforce for species protection.” —NGO Employee
Gaps in water use and supply data across the state make water stewardship more challenging. To manage water effectively, decision-makers need to know how much water is in the system, how much is being used, where and when it is being used, and who is using it. For example, water managers need to create water budgets to track the amount of water coming in and out of the system; however, many do not have sufficient data to make accurate water budgets.
A Tribal representative reflected on the impacts of infrequent groundwater elevation data collected through the California Statewide Groundwater Elevation Monitoring (CASGEM) program. “California is very behind in managing groundwater… We don’t have the data to generate well defined hydrological model[s] to evaluate management decisions and for us [our Tribe] to have a good understanding of the impacts of groundwater extraction on our resources. We are Salmon People and having water in our rivers and streams is critically important.” (Tribal Government Representative)
Critical data gaps in California as identified by interviewees, include:
- Groundwater data
- Water rights diversion data
- Stream gage data
- Evapotranspiration (ET) estimates
- Well locations and levels, especially domestic wells
- Customer-level urban water use and billing data
- Small-scale farm water use data
- Water quality data, especially in small community water systems and irrigation canals
- Ecological data on the impacts of groundwater pumping
- Projected impacts of climate change and drought on surface water and groundwater levels