Reclaimed Water Distribution Evaluating Costs and Benefits
Judi Gladstone Seattle Public Utilities April 23, 2009
The Purpose of the Analysis
Evaluate benefits and costs of delivering reclaimed water to North Seattle along with alternatives that provide the same benefits.
Seattle Regional Water System
Reclaimed Water Distribution
Assessing Project Demand z Identify
potential customers with significant non-potable water uses • • • • •
Golf Courses Cemeteries Parks Schools UW
z Measure
use
or estimate non-potable water
Top 11 Potential Users Evergreen-Washelli Cemetery* Seattle Golf and Country Club*
Irrigation Potential Reclaimed Water Consumption University of Washington Pond
Cooling
Sand Point Country Club* Jackson Park Golf* Holyrood Cemetery* Woodland Park and Zooª Greenlake Nile Golf & Country Club* Calvary Cemetery Acacia Memorial Park* 0.00
0.05
0.10 0.15 0.20 6 Month Average MGD
0.25
0.30
Framework for Analysis z Water
Reuse Foundation- framework for conducting Full Benefit/Cost Analysis of Reclaimed Water Projects z 10 steps
Full Benefit/Cost Analysis- 10 steps 1.
Define baseline conditions
2.
Define project and alternatives
3.
Identify benefits and costs
Full Benefit/Cost Analysis- 10 steps 4.
Determine appropriate type of analysis of benefits
5.
Quantify units for quantitative analysis
6.
Assign values associated with benefits and costs
Full Benefit/Cost Analysis- 10 steps 7.
Describe benefits for qualitative analysis
8.
Summarize
9.
Describe uncertainties, biases, omissions
10.
Sensitivity Analysis
SPU Analysis z Define • •
the Base Case
Location of potential users Water supply being replaced
z Identify
and analyze alternatives for achieving project benefits
Problems to be Solved z Poor
habitat for aquatic species in local creeks Low creek flows z High temperature of water z
1,400,000 Actual and Forecast Water Consumption Per Capita: Seattle & Non-CWA With and Without Programmatic Conservation after 2005 Population
180 180 160
Non-Rev
1,200,000
Total Consumption
150
1,000,000 Billed GPD per Person Consumption
120
120 100
Actual GPD per Person
800,000
WITHOUT Conservation
80
GPD per Person WITH Conservation
90
600,000
60
40
60
400,000
20
0
30 1990
0 1975
1995
2000
2005
2010
2015
2020
2025
2030
2035
2040
2045
2050
2055
2060
200,000
0
1980
1985
1990
1995
2000
2005
Population
GPD per Person
Annual MGD
140
Past Water Forecasts 240 220 200 180
140
Boeing Recession
120
Actual Annual
1992 Drought & Mandatory Curtailment
5-Year Moving Average
100
1967 SWD Forecast
80
1973 RIBCO Forecast
60
1980 Complan Forecast Medium 1980 Complan Forecast Medium-Low
40
1985 Complan Forecast-Medium 20
1993 WSP Forecast 2005
2000
1995
1990
1985
1980
1975
1970
1965
1960
1955
1950
1945
1940
1935
0 1930
Annual MGD
160
SPU Analysis continued z Identify
and quantify project benefits and costs z Conduct benefit-cost or cost effectiveness evaluation z Conduct sensitivity analysis z Conduct perspectives analysis
Infrastructure Costs z Treatment
to reclaimed water standards
z New
pipes and pumps to deliver reclaimed water from production to users
z Retrofitted
users to accommodate reclaimed water (separate system)
Supply Alternative Analysis (2007) 1.0 High Value Low Cost
0.9
High Value High Cost
0.8
Conservation*
Value Score
0.7
SF Tolt 1695
0.6
Reclaimed Water Value: 0.478 - 0 Cost: $5.80 - $1
Lake Youngs Drawdown SF Tolt 1660
0.5 0.4
Cedar Dead Storage
0.3
North Fork Tolt
Snoqualmie Aquifer
0.2 Low Value Low Cost
0.1
Low Value High Cost
0.0 0.0 a
0.5
1.0
1.5
2.0
2.5
3.0
Levelized Unit Cost (PVm$/PVmgd)a
Calculated assuming all sources online in 2050. *4 mgd conservation program begins in 2045 and phases in over a 10-year period.
3.5
4.0
Conclusions z In
reclaimed water it is Location, Location, Locationz
Problems to be solved & benefits gained vary from area to area
z Decisions
about reclaimed water need to be based on analysis of all costs and benefits z
Need to invest limited resources wisely
Areas of Research 1. 2. 3. 4. 5.
Willingness-to-Pay Alternative solutions Reliable stream flow data Groundwater continuity Carbon footprint