Long Term Water Supplies Background
How TVWD Arrived At The Tualatin Basin Water Supply Project
As part of its ongoing Master Planning process to develop an additional, cost-effective water supply source that will meet our needs for the next 50 years, the TVWD Board looked at seven different scenarios (see table below), with combinations of all, some, or no water from the Portland Water Bureau, the Joint Water Commission (JWC), and the Willamette River Drinking Water Plant. The Board weighed the attractiveness of each option according to financial criteria as well as non-financial criteria, such as: drinking water quality, public acceptance; complexity of partnership agreements; source reliability and redundancy, fluoridation and community impacts.
Scenarios Considered
Scenario | Source Capacity (million gallons per day) | |||
Portland | JWC | Willamette | ||
1A | Willamette without Partners, JWC (10 MGD), Portland (Supplying Metzger Area) | Metzger | 10 | Balance |
1B | Willamette with Partners, JWC (10 MGD), Portland (Supplying Metzger Area) | Metzger | 10 | Balance* |
2A | Willamette without Partners, JWC (10 MGD), No Portland | 0 | 10 | Balance |
2B | Willamette with Partners, JWC (10 MGD), No Portland | 0 | 10 | Balance* |
3 | JWC/TBWSP (Most), Portland (Existing Without Peak) | Existing Without Peak | Balance | 0 |
4 | JWC/TBWSP (All) | 0 | Balance | 0 |
5 | JWC/TBWSP (Most), Portland (Metzger**) | Metzger** | Balance | 0 |
**Preserves the option to serve Metzger with JWC in the future | ||||
6 | Portland (Most), JWC (10) | Balance | 10 | 0 |
Option 5 is the Board's selection that was selected | Options 2A, 2B and 4 were discontinued earlier in the process due to Board direction | |||
| *mgd - Million Gallons per Day | ||||
Portland: Portland Water Bureau
JWC: Joint Water Commission
Willamette: Willamette River Water Treatment Plant
TBWSP: Tualatin Basin Water Supply Project