Rainbow is connected to Springfield Utility Board (SUB) and Eugene Water and Electric Board (EWEB), allowing each utility to provide some assistance to the others in the event of a regional emergency. SUB and EWEB are supplied from a combination of groundwater and surface water sources. Rainbow relies on groundwater alone for our normal water supply, although one well is subject to influence from the McKenzie River so it is classified and treated as surface water.
Water is pumped from underground and stored in two hilltop reservoirs. These reservoirs maintain pressure in the pipes as water use fluctuates during the day, and they provide an emergency reserve for fire protection. We deliver the treated water through transmission and distribution piping to various neighborhoods and areas of need.
We collect over 100 samples per year, testing our wells and system monitoring points on a regular basis, to look for harmful chemicals or bacteria and verify the water system is operating properly.
Last year, Rainbow's water was supplied from four wellfields:
I-5 - Two wells which provided 51% of our April-September (Spring and Summer) water demand and 52% of our Fall and Winter (October-March) water demand in 2021.
Chase - Five wells which provided 32% of our spring/summer demand and 44% of our fall/winter demand. We raise the pH of the water from this source to help control corrosion.
Q Street - One well providing up to 4% of our summer supply.
Weyerhaeuser - Three wells jointly owned by SUB provided 13% of our spring/summer demand and 3% of our fall/winter demand. We started corrosion control treatment to raise the pH in 2021.