The watersheds in the hillsides surrounding the Valley (in the Ag Watershed zone) supply 100% of reservoir water and 60% of the Valley’s groundwater.
Trees in the watershed capture and filter rainwater:
“Oak woodland canopies capture 20-30% more rainfall than do grasslands, and their contribution to organic matter in the soil improves its water holding capacity… soils under oak woodland canopy are able to absorb and hold greater amounts of rainfall than equivalent soils with only annual grassland cover… Oaks and other vegetation also help reduce soil contamination by absorbing heavy metals, fertilizer nutrients, and pesticides from the soil and intercepting sediments containing these pollutants, thereby preventing these materials from reaching surface waters.” — The 2010 Napa County Voluntary Oak Woodland Management Plan: https://www.
How much water are we using?
In 2017 residents relied on the reservoirs in our watershed for 65% of the domestic water used by Napa and cities north. Agriculture used 68% of the groundwater pumped out for vineyard irrigation and winery production. On average, producing 1 gallon of wine requires 7 gallons of water.
org/files/managed/Document/ 9230/Napa%20County% 20Groundwater% 20Sustainability%20Annual% 20Report%20-%20Water%20Year% 202017_Final-sm.pdf
Napa Valley residents and our agriculture depend upon the water captured by oak woodlands in our hillsides. By protecting our woodlands– NOW and for generations to come — Measure C protects both the rights of all homeowners to turn on their tap and have water, and the ability of our hillside watersheds to recharge the groundwater that is critical for Napa Valley’s agriculture.
We are currently in balance with our groundwater use, taking out about the same amount as we use for cities and agriculture, according to a study of well levels from 1988-2015 initiated by the County. As we take out more for growth, where will the water come from? Currently there is NO STATED LIMIT for how many acres of woodlands can be removed for ag development.
Measure C sets a limit for oak woodland loss to development— the 795-acre limit was determined by the Napa Valley Vintners in collaboration with the Watershed Initiative Committee. This limit allows for vineyard development predicted by the County’s General Plan. When the 795 acre limit is reached, a permit from the county is needed to remove oaks, just as a permit from the city is needed now for oak removal in city limits. Do we want more development by large, non-local corporations such as Walt Ranch, which can have 35 parcels with roads homes and buildings, and was approved by our Supervisors to remove 14,000 oaks? Measure C is an initiative because the Supervisors aren’t willing to work on protections.
Yes on Measure C relies on volunteer and local citizens, and it’s proof that parts of our democracy still work. Please share this grassroots effort with your networks, and thank you for your concern and support.