If we continue to use water wisely, Scotts Valley's water supply can support our community's future, including the growth the city is currently experiencing.
The Scotts Valley Water District has been planning for future water needs for decades, beginning with the District's first Urban Water Management Plan in 1998. The Urban Water Management Plan, which is updated every five years, evaluates water demand and supply in the next 25-year period. The current plan was completed in 2015 and makes estimations through 2040. It will be updated again in two years.
By 2040, Scotts Valley’s population is projected to be double of what it was in 1985, yet the total amount of the potable water used is estimated to stay roughly the same. Actually, total groundwater pumping in the Scotts Valley area has decreased 46 percent from 2000 and, since the early 2000s, and groundwater levels have stabilized, following years of depletion.
How is this possible? Customers have become more efficient with their water use (thank you!). Currently, District customers use an average of 56 gallons per person, per day, including potable water used to irrigate outdoor landscaping. By comparison, a state report showed, on average, Californians used 85 gallons of water per person per day in 2016. An average single family home uses approximately 80,000-100,000 gallons per year, while a unit in a multi-residential complex uses only about 50,000 gallons a year.
Also, the District has implemented smart practices and technologies to manage water demand and supply more efficiently: adding recycled water to our supply portfolio, substituting potable water use for irrigation, installing stormwater groundwater recharge systems, and deploying automation to run treatment and distribution processes more effectively.
Another contributor to the reduction in the groundwater use in Scotts Valley area is a significant decline in industrial and remediation pumping, which comprised 20-25 percent of the total demand in 1990s.
The biggest challenge for the District is the uncertainty of rainfall, which is imperative to groundwater replenishment — 2014 went on record as driest year in the last 40 year history with 48 percent of the average rainfall (20 inches) and 2017 as the second wettest with 188 percent (80 inches). It is predicted that the future will bring more extreme weather patterns and negatively impact the natural recharge capability.
Only about 30 percent of precipitation reaches aquifers even in a normal rainfall year. Severe storms cause higher rates of runoff and less direct recharge, and 70 percent of annual precipitation is returned to atmosphere by evaporation and released from plants by transpiration.
To complement natural recharge and prepare for climate variability, the District is considering a supplemental supply project using a highly treated recycled water for groundwater replenishment. A feasibility study for the concept showed good outcomes and the next step is an environmental study, which likely will occur during this fiscal year. The project, which has a $15-20 million price tag and is anticipated to be funded through grants and already-approved water rates, could be built in the next three to seven years..