Why are streams that used to flow in the summer now dry?

Reaches of the Napa River have over many decades (since the 1930s) experienced low to no-flow conditions during the summer-to-fall period for a variety of reasons. Stream flow is very dependent on seasonal rainfall, small dams (both legal and illegal) that have been constructed to block stream flow, withdrawals of surface water (both legal and illegal) from the creeks, as well as reduced groundwater discharge into the stream channel. The duration of annual no flow days varies from year-to-year and increases during extended droughts as during recent years.

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1. Is groundwater quality currently being monitored?
2. Is there a link between groundwater and surface water, and if so, how will it be managed?
3. What is a water budget?
4. What is irrigation system efficiency and what factors affect the efficiency?
5. What is the current status of the Napa River for impairment under the Clean Water Act?
6. How is climate change taken into account in considering and planning for groundwater sustainability?
7. How does the groundwater basin affect flows within the Napa River?
8. If groundwater conditions are so good, why did my well go dry?
9. If depth to groundwater is so shallow, why do wells seem to be getting deeper to find water?
10. Why are streams that used to flow in the summer now dry?
11. Since surface water and groundwater are connected, isn’t groundwater pumping dewatering the Napa River and threatening our remaining native fish populations?
12. Are you doing anything about well problems in the county like the Petra Dr / Soda Canyon area?
13. Return to the Groundwater FAQ page