Seattle has some of the best-tasting, highest-quality water in the nation. Our pristine water comes from 103,000 protected acres in the Cascade foothills east of Seattle via the Cedar River Watershed (70%), the Tolt River Watershed (29%), and wells at the Highline Wellfield (1%). From these sources, water travels by large pipelines to Seattle. Water is cleaned, treated, and continually tested as it travels through the system to ensure that it is of the highest quality. Visit Seattle's Regional Water System Virtual Map and the Cedar River Watershed Education Center to learn more.
To make the most of this precious resource, we use water-efficient technology in our buildings and water-conserving practices to care for our landscaping.
We use high-efficiency plumbing fixtures on campus, including low-flow showerheads, urinals and faucet aerators, and dual-flush toilets. All cooler and freezer equipment on continuous-loop water-cooled systems were replaced with water-saving refrigerant systems.
We use drip irrigation to eliminate water lost from wind, overspray, runoff, and evaporation. An irrigation sensor monitors the flow rate, allowing us to detect leaks quickly. We’ve programmed the irrigation system to run in the evenings, when watering is most efficient, and sensors prevent the irrigation system from turning on when it’s raining.
We group plants with similar watering requirements in the same zone, and our plants are drought tolerant. A layer of wood chips around the plants refracts the suns energy in several directions and helps to regulate surface soil temperature and reduce water loss to evaporation.
The lawns are aerated to increase water and air penetration, encouraging a deeper, healthier root system that is better able to withstand longer periods between watering. We mow the grass to 3 inches, which shades the soil, reduces evaporation, and decreases water requirements. Finally, we leave grass clippings on the lawn to decompose, adding organic matter to the soil and increasing its water-holding capacity.