Portland Drinking Water

1. Portland Drinking Water

2. Bull Run--Source • primary drinking water supply for Portland • Located 26 miles from downtown Portland in Sandy River basin, in Mt. Hood National Forest

3. Drinking Water • Protected in 1892 for Portland drinking water supply • Serves more than 900,000 residents in the Portland • 2001: protection boundary extended by federal law • Groundwater available as a back-up supply since 1986 • used to meet peak water demand during summer months • emergency source of supply when Bull Run is not available ie. during Feb 1996 flood, used to meet water demands for several days due to turbidity in Bull Run reservoirs

4. Turbidity: measure of how much sediment is in water • Groundwater: underground in soil, aquifers, springs, etc.

5. The Bull Run Watershed • 102 square-mile area • water from rain and snowmelt that flows to the Bull Run River and tributaries • river drains into two reservoirs -- more than 17 billion gallons stored

6. Powell Butte

7. Powell Butte • reservoir can hold 50 million gallons of water • In 1925, the Portland Water Bureau purchased Powell Butte for $135,000 as a site for future reservoirs. • In 1981 the first reservoir was installed. • In 1990, Powell Butte Nature Park , the second largest in the city, was dedicated.

8. Mt. Tabor & Washington Park Storage Reservoirs • reservoirs receive water by gravity flow or pumping • Capacity of approximately 220 million gallons • Security surveillance cameras monitor the reservoirs 24 hours per day • Open reservoirs must be cleaned every six months • All 3 reservoirs store 3 days’ worth of water

9. Testing Portland Water • Performs 54,400 analyses on 11,800 water samples each year • Samplers collect water from the watershed reservoirs, in-town reservoirs, the distribution system , groundwater and consumers' taps

10. Treating Portland Water • Currently not filtered • Meets the filtration avoidance criteria of the 1989 Surface Water Treatment Rule • Waiver from the requirement to filter since 1991 • Bull Run water is very soft: typically ranges from 1/3 to ½ a grain of hardness per gallon • Portland's groundwater hardness is approximately 5 grains per gallon -- considered moderately hard • No fluoride added

11. Disinfection • Portland's water: chloramination • chlorine to disinfect the water • ammonia to ensure that disinfection remains • New federal regulations may require additional treatment processes by 2013

12. pH adjustment for corrosion control • January 1997: Portland Water Bureau began corrosion control treatment • raise pH of the water so less likely to leach metals • target pH range is 7.8 to 8.0 • at least a 50 percent reduction in lead at the tap with pH adjustment

13. Safe Drinking Water Act (SDWA) 1974 • Set the standard for public drinking water nationally • In 1986 Act amended: increase requirements for safety testing • In 1996 Act amended: increase source protection, capacity to carry water to the public

14. How water gets to the sink • to Portland by gravity • Through water mains to all parts of the city -- run beneath sidewalks and streets to individual homes and businesses • a smaller pipe travels to the water meter at each home or business not on a well • water passes through the meter on its way to your home to measure the amount of water your house uses • mains and the water meter owned by the City of Portland • aterenters pipes which are the owned by property owner. Those pipes deliver water to your tap.