Irvine Ranch Water District s Groundwater Banking Program

Transcription

1 Irvine Ranch Water District s Groundwater Banking Program National Water Research Institute Drought Response Workshop October 8,

2 Today s Discussion Introduction to IRWD Drought Preparedness at IRWD: a) Water Use Efficiency b) Diversification of water supplies c) Groundwater Banking Questions 2

3 Introduction to IRWD 3

4 About IRWD A special district governed by a publicly-elected board. IRWD customer base: Residential population: 350,000 Daytime population: over 500,000 Service connections: 102,381 IRWD service area: 181 square miles (20% of Orange County) All or part of six cities and unincorporated county: Irvine Tustin Orange Lake Forest Newport Beach Costa Mesa 4

5 About IRWD District Organization: Board of Directors Water Operations General Manager Recycling Operations Public Affairs Water Quality Customer Service Water Resources Finance and Treasury Human Resources Engineering 5

6 Our Four Lines of Service IRWD Services and System Statistics: Potable Water: Four treatment plants, 25 wells, 1,500 miles of pipelines. Sewage Collection: Nearly 1,000 miles of sewage collection pipelines. Recycled Water: Two water recycling facilities (28 MGD MGD) and approximately 500 miles of recycled water pipelines. Urban Runoff Treatment: The San Joaquin Marsh and 31 built and planned man-made wetland treatment sites. 6

7 Drought Preparedness through Water Use Efficiency 7

8 Residential GPCD Acre-Feet Per Acre Per Year Water Use Efficiency Effective Water Use Efficiency Initiatives: Allocation-based rate structure. Pricing signal encourages conservation Landscape irrigation management. New technologies: Weather-based irrigation controllers More efficient interior devices Tiered Rate Structure 1991 Residential Accounts 20% El Nño Residential GPCD AF/Acre/Yr 2007 Record Low Rainfall " Landscape Accounts 50%

9 Drought Preparedness through Water Supply Diversification 9

10 Acre-feet per Year IRWD s Water Supply Portfolio Today IRWD has a diverse, reliable water supply with appropriate redundancy. 120, Total Water Supply, By Type 100,000 80,000 60,000 Imported Water, 22% Clear Groundwater, 32% Other, 3% 40,000 20, Fiscal Year Recycled Water, 24% Treated Groundwater, 18% * Excludes IRWD water banking (88,000 AF storage) Conversion: 1 acre-foot (AF) = 325,851 gallons 10

11 Increasing IRWD s Water Supply Reliability Developing diverse supplies to improve reliability: High quality groundwater Treated groundwater Recycled water Imported water Long-term contingency storage: Why? Augment water supplies over a three-year period in severe drought or other supply interruption conditions. How? A comprehensive groundwater banking program of at least 88,000 acre-feet of banked water. 11

12 IRWD s Groundwater Banking Program 12

13 IRWD Groundwater Banking Program Program Overview: IRWD has developed water banking projects in Kern County: acres of recharge basins - Seven production wells; 17,500 AF per year - 50,000 AF of storage capacity (Strand Ranch) - Expanding to 88,000 AF (Strand + Stockdale) Partnerships in place with: - Rosedale-Rio Bravo Water Storage District (Operations) - Buena Vista Water Storage District (Water) - Metropolitan Water District of Southern California (Exchange / Conveyance) 13

14 IRWD Water Bank Project Location Location ideal for water banking and conveyance: Strand Ranch: 611 acres total; 502 acres of recharge basins (acquired in 2004) Stockdale West Ranch: 325 acres; 259 acres of recharge basins (acquired in 2010) 14

15 Sources of Water for Storage in Water Bank Goal: To secure surplus water supplies during wet periods Water from the State Water Project (SWP): Unbalanced exchanges of Table A water from SWP contractors and 2011 Central Coast Water Authority Antelope Valley East Kern Water Agency IRWD s Jackson Ranch (883 acres) - Table A water, a portion of which can be banked by IRWD - Participation rights in the Kern Water Bank (7,600 AF of storage) Orchard at the Jackson Ranch Water from Non-SWP Supplies: Kern River Flood Flows (via Rosedale); IRWD retains 20%. Kern River High-Flow Pre-1914 Water (via Buena Vista Water Storage District); IRWD retains 50%. Other Wet-Year Exportable Supplies (as available). The CVC on the Strand Ranch 15

16 Getting Water out of the Water Bank IRWD s Agreements with Metropolitan Water District: 1) Coordinated operating and exchange agreement (2011) Allows IRWD to secure SWP water - Water is delivered to IRWD through exchange - MWD can borrow supplies from IRWD - MWD has option to store the water in Southern California 2) Wheeling agreement (in process) Allows IRWD to exchange non-swp water supplies with MWD for delivery to IRWD s service area - MWD cannot borrow these supplies 16

17 Measuring Success Meeting IRWD s Reliability Goal of 88,000 AF of storage 36,000 AF of water already in storage in IRWD s water banking projects in Kern County. - Half of this water will need to be returned to IRWD s unbalanced exchange partners (2-for-1). - IRWD will have achieved 20% of its 88,000 AF storage objective. - IRWD and partners mutually benefit from recharge and recovery facilities. - Cost objective: < MWD s Tier 2 water. First water to the Stockdale West Ranch - Next step: Move water from Strand Ranch to Southern California. 17

18 Cost of Water ($/AF) Cost of Water out of the Water Bank Comparison of Strand Ranch Water with Metropolitan Rates (2013) $3,500 $3,000 $2,841 $2,500 $2,000 Treatment Wheeling Charges $1,500 $1,000 $997 $847 $864 OM&E Cost of Water Net Capital (Including Land) Less Residual Values $500 $- MWD Allocation Penalty MWD Full Service Tier 2 MWD Full Service Tier 1 Strand Ranch Water Source 18

19 IRWD Contact Information Paul Cook General Manager phone: (949)