In May, our newsletter examined the concept of the “water year,” the part of the year when the majority of our precipitation occurs. It begins in the fall of the year and ends in the spring of the following year, encompassing the months of October through March. About 73% of our precipitation falls during this time.
Our climate is classified as a Mediterranean climate – wet winters and dry summers with great variability in the pattern. As you may recall, our water year over the past 20 years has averaged 13.24 inches. This last year we were just under that amount, at 13.16 inches.
So, as we enter the new water year, how did we fare over the remainder of the spring and summer months with regard to precipitation?
While we experienced a few wet months this summer, Ashland’s total precipitation over this time period was .87 inches below the norm. That’s not wildly off, as you can see in this graph comparing this year’s precipitation to the average — but we are still in drought.
Take a look at this map of the state of Oregon. As of this September, we’re still in moderate drought.
These conditions are unlikely to let up anytime soon —The forecast for the region is for drought to persist. Read on for some thoughts about how we prepare for the long-term as our weather shifts due to climate change.
The Future of Ashland’s Water
Predicted Effects of Climate Change on Water Management in the Ashland Creek Watershed – Future Changes in the Quantity and Timing of Demand Requires Conservation Efforts Today
Demand predicted to outstrip supply in the early 2050s.
In the July 2023 ACC Water Conservation News, we mentioned that the City is preparing an update to the state’s Water Management and Conservation Plan. The update includes a focus specifically on the effects of climate change to water supply and water demand. An update to the Ashland watershed’s climate modeling made by Oregon Climate Change Research Institute indicates that both the timing of when rain will enter our systems and the demand for water will both change. This information indicates to us that Ashland will need to increase conservation efforts to ensure a steady supply of water for the future.
Temperature Will Drive Up Demand
Water demand is projected to grow as temperatures increase, with the most noticeable increases in the spring months of March, April, and May and the fall months of September, October and November. Much of our consumption is for landscaping. Increased water demand for outdoor use occurs as soon as temperatures go above 70, but are not further increased above 90 or 95 degrees. So, while summer demand will remain relatively unchanged, the increase in water demand driven by higher temperatures in earlier and later months will add significantly to outdoor water use.
These increases in total demand don’t take into account potential population growth, which also causes an increase in year-round demand.
ore precipitation as rain, less as snow affecting supplies
Future climate change effects on the water supply won’t change annual precipitation totals much. However, more precipitation will fall as rain rather than snow, so runoff that fills our reservoir will come earlier and be diminished the rest of the year. While this can help support early demand in the spring, the expected lower late spring, summer and fall stream flows into Reeder Reservoir will push the city to rely on our TAP (Talent, Ashland, Phoenix regional water supply system) for longer periods of time each year.
Two results of this increased outdoor consumption are higher total annual demand and a change in when the watershed and Ashland’s Reeder Reservoir can support most of our use. The other major source of water supply is water stored in Lost Creek reservoir and delivered through the TAP pipeline. While Talent Irrigation District water has been a significant source of water in late spring and early summer, its supply has become less reliable due to heat and drought and isn’t expected to be a reliable water source in the future.
Solutions Will Take Years to Implement
These increases in total demand are in addition to increases due to population growth, which also causes an increase in year round demand. The forecasting report estimates that demand will outstrip supply by the early 2050s. What can we do? A municipality can affect these patterns by either purchasing more supply or by decreasing demand, or both. There may come a time when new supplies are not available, so it makes sense to start work now to decrease demand as soon as possible. It will take years for residents to develop new conservation habits and to transition our gardens and landscaping to more drought- and heat-tolerant plantings and irrigation systems.
The Important Role of Conservation
The City has had very successful conservation programs that were part of a comprehensive water conservation plan. For most of the early 2000s the City employed a dedicated water conservation staff person, but that position has been eliminated in recent years. Today, the city has a contract for two days per week of water conservation staffing from the Medford Water Commission.
While a variety of conservation incentives to customers remain in place, Ashland lacks the more robust outreach and education programs needed to mitigate expected climate effects on future water demand. A new plan with new goals and policies, supported by staff to promote current and expanded programs will be necessary to reduce these newly recognized demands on our water supply system. Reinstating the Water Conservation Specialist position will help achieve that effort to prepare for the future.
