Transcript View Video - Marin Municipal Water District

Water Resources Plan 2040 Update
Draft Conclusions and Recommendations
November 22, 2016
Analysis Demonstrates that MMWD’s Proactive Actions
Have Significantly Improved Water Supply Resiliency
•
1979: Built Soulajule Reservoir
•
•
1981: Recycled water program
•
•
Increase storage by 10,000 AF
Saves 600 AFY of potable water
1982: Expanded Kent Dam
•
•
Raised 45-feet
Doubled storage capacity to 32,900 AF
1993: Aggressive conservation program &
conservation-oriented rate structure
• Increased supply imported from Sonoma
County (provides 25% of water supply)
•
Increased Storage Implemented Over Time
 Improved Resiliency
Expanded
Kent Lake
90,000
Reservoir Storage, acre-feet
80,000
70,000
Nicasio
Reservoir
60,000
Soulajule
Reservoir
50,000
Kent
Lake
40,000
62,700
30,000
Expanded Bon Tempe
20,000 Alpine Reservoir
Lake
10,000
0
79,570
9,650
1941
52,100
29,700
13,650
1948
1954
1960
1979
1982
Efficient Water Use has reduced Demand
and Improved Resiliency
40,000
200,000
Population
180,000
160,000
30,000
140,000
120,000
20,000
100,000
80,000
60,000
10,000
40,000
20,000
0
0
Fiscal Year
Population
Water Production (AF)
Water Production (AF)
Process for Conducting Resiliency Analysis
Identify Events,
Futures, and
Options
Evaluate and
Refine Preliminary
Options
Identify Gaps /
Needs (Shortfalls
Under Event /
Future
Conditions)
Develop /
Evaluate / Refine
Alternatives to
Address Gaps /
Needs
Events and Futures
Drought
Climate Change
Wildfire
Earthquakes
Water Quality
Landslides
• Historical recorded droughts and 6-year drought
Greatest
Stressor
• Four climate change hydrology sets developed by USGS
• Impacts to water quality at Kent, Bon Tempe, Alpine Lakes
• Outages to Bon Tempe WTP, San Geronimo WTP, and imported supply
• Impacts to Kent and Alpine Lakes, Nicasio Lake, imported supply
• Outages at Bon Tempe WTP, San Geronimo WTP, Alpine Lake
Resiliency Options
Water Use Efficiency
 Reuse
 Expand SCWA Conveyance
 Expand Storage
 Water Purchases and
Groundwater
 Desalination
 Emerging Options

Key Information For Each Option
Description
Facilities Required
Sizing and Cost
Yield and Reliability (Average and Dry Year)
Implementation Considerations
Conceptual Map / Schematic
Preliminary Evaluation Criteria
Cost
Institutional Complexity
Local Control
Environmental Stewardship
Technical Complexity
Reliability
Public Support
Options Evaluation

Developed 40 resiliency options

Used decision score and options costs to evaluate the 40 resiliency options in
a tradeoff curve



Decision Score (benefits) vs. Cost
Options with lower cost/higher benefits were selected for alternatives development
High scoring options were selected for alternatives development and
grouped into the following resiliency categories:





Expand existing programs
Minimize infrastructure
Dry Year actions
Maximize reuse
Maximize resiliency
Resiliency Analysis
Six-Year Severe Drought Results
Use storage reserves
30,000
25,000
AFY
20,000
15,000
10,000
5,000
1
2
3
4
Year
Supply
Deficit
Demand
5
6
Resiliency Alternatives: Group A



Meets demands during 6-year drought
No demand reduction
Maintains storage reserves
Dry Year Yield
(AF)
Alternative
Options
Dry Year Actions
• Enhanced Conservation
• Spot Market Transfers
6,000
Maximize Reuse
• Regional IPR
7,900
Maximize Resiliency
•
•
•
•
Enhanced Conservation
Kastania Pump Station Upgrade
Santa Rosa Plain Conjunctive Use
Watershed Management
11,000
Resiliency Alternatives: Group B



Meets 4 year drought demands
Encroaches storage reserves in years 5 & 6 of 6-year drought
To maintain storage reserves, requires demand reductions
Dry Year Yield
(AF)
Alternative
Options
Expand Existing Programs
• Enhanced Conservation
• Santa Rosa Plain Conjunctive Use
• Watershed Management
up to 1,200
Minimize Infrastructure
• Enhanced Conservation
• Kastania Pump Station Upgrade
• Santa Rosa Plain Conjunctive Use
3,900
Draft Conclusions and Recommendations
Conclusions & Recommendations

MMWD’s resiliency actions provide significant benefits

These resiliency actions will enable the district to survive a
number of futures

Alternatives exist to address resiliency needs under the most
extreme conditions

Adaptive Resiliency:



Continue water efficiency programs at current level; increase if necessary
Investigate low- or no- infrastructure alternatives (groundwater
exchange)
Track hydrologic conditions and demand patterns
Next Steps
WRP 2040: Public Outreach
Nov 22, 2016 DOC
• Draft Conclusions and Recommendations
Dec 7, 2016 DRTF
• Public Workshop
Jan 20, 2017 DOC
• Admin Draft Report
Feb 2017 Board
• Public Review Period
Mar 2017 DRTF
• Review of public comments
Apr 2017 DOC
• Final WRP 2040
Water Resources Plan 2040 Update
Draft Conclusions and Recommendations
November 22, 2016