Upload
spencer-clarke
View
218
Download
0
Tags:
Embed Size (px)
Citation preview
Eastern Snake Plain Comprehensive Aquifer Management Plan
A Positive Path Forward
Hal N. Anderson
June 11, 2009
-3
-2
-1
0
1
2
3
4
19
16
19
20
19
24
19
28
19
32
19
36
19
40
19
44
19
48
19
52
19
56
19
60
19
64
19
68
19
72
19
76
19
80
19
84
19
88
19
92
19
96
20
00
Std
An
om
ali
es
Re
lati
ve
to
19
61
-19
90
PNW
CA
CRB
GB
Regionally Averaged Cool Season Anomalies
(Source-U.W. Climate Impacts Group)
Eastern Snake Plain Aquifer Model Water Budget
Sum of Historic Diversions: Snake River abv King Hill
5,500
6,000
6,500
7,000
7,500
8,000
8,500
9,000
9,500
10,000
1928
1932
1936
1940
1944
1948
1952
1956
1960
1964
1968
1972
1976
1980
1984
1988
1992
1996
2000
2004
2008
Water Year
An
nu
al V
olu
me
(100
0 A
c-ft
)
ANNUAL DIVERSION
4 YEAR MOVING AVERAGE
AVERAGE ANNUAL SPRING DISCHARGE TO SNAKE RIVER BETWEEN MILNER AND KING HILL
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
1902
1908
1914
1920
1926
1932
1938
1944
1950
1956
1962
1968
1974
1980
1986
1992
1998
2004
Water Year
Dis
ch
arg
e -
Cu
bic
Fe
et
pe
r S
ec
on
d
1902-2008
Background • ESPA Framework Plan Process Initiated 2006, by SCR
136.• ESPA Framework Plan Developed and Adopted in 2007,
HCR 28.• Advisory Committee Convened (2007) • ESPA Advisory Committee Recommendations
Developed (2008)• Board Adoption of the ESPA Plan, January 29, 2009.• 2009 Legislature approved HB 264 approving ESPA
Plan, Governor signed into law April 23.
Framework Plan
Recognized that water supply and demand were out of balance in the aquifer and the Snake River, making more deliberate and coordinated management of surface and ground water on the ESPA a necessity.
Objectives for ESPA Management• Increase predictability for water users by
managing for reliable supply.
• Create alternatives to administrative curtailment.
• Manage overall demand for water within the Eastern Snake Plain.
• Increase recharge to the aquifer.
• Reduce withdrawals from the aquifer.
Historic Flow Volume: Snake River at King Hill
0
2,000
4,000
6,000
8,000
10,000
12,000
14,000
1910
1914
1918
1922
1926
1930
1934
1938
1942
1946
1950
1954
1958
1962
1966
1970
1974
1978
1982
1986
1990
1994
1998
2002
2006
Water Year
An
nu
al V
olu
me
(100
0 A
c-ft
)
ANNUALFLOW
4 YEAR MOVING AVERAGE
Historic Flow Volume: Snake River at Milner
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
19
10
19
14
19
18
19
22
19
26
19
30
19
34
19
38
19
42
19
46
19
50
19
54
19
58
19
62
19
66
19
70
19
74
19
78
19
82
19
86
19
90
19
94
19
98
20
02
20
06
Water Year
An
nu
al V
olu
me
(1
00
0 A
c-f
t)
ANNUALFLOW
4 YEAR MOVING AVERAGE
Management Options Components Estimated Average
Supply (best information)
Estimated Cost (best information)
Hydrologic Impacts Timeline for implementation
Weather Modification (Idaho only)
60,000-190,000 AF/yr (increase yield by 3.5- 7%)
$250k -$700k/yr Potential supply increase in headwater snowpack. Increased natural flow, and increased reservoir storage.
1-to-2 years
Aquifer Recharge (no construction option – use excess natural flow for supply)
70,000 AF/yr
(50 KAF from Snake and 20KAF from Wood)
$8/AF wheeling fee ($560,000/yr)
No capital cost
Above American Falls – improved natural flow later in season. Some improvement to reaches above and below Milner with current facilities at NSCC and Wood River system
1 year
Salmon flow exchange
102,000 AF/yr (varies from 0-to-205KAF based on water supplies)
$185M up-front cost (need to acquire 205KAF+20%, assume $750/AF)
Increase in storage availability for conversion or recharge projects. Reduces releases past Milner.
5 years due to water right purchases
Costs are preliminary estimates for budget purposes only
Management Options Components Estimated Average Supply
(best information)Estimated Cost (best information) Hydrologic Impacts Timeline for
implementation
Minidoka Enlargement 50,000 AF/yr $250M capital cost
Annual O&M at 1% of capital cost ($2.5M/yr)
Reliable Storage supply for conversion, recharge or other projects
10 years
New Storage above American Falls
100,000 AF/yr $500M capital cost
Annual O&M at 1% of capital cost ($5M/yr)
Reliable Storage supply for conversion, recharge or other projects
30 years
Aquifer Recharge - Infrastructure required - using excess natural flow
400,000 AF/yr $75M
Annual O&M at 1% of capital cost ($750K/yr)
Annual wheeling costs of $8/AF ($3.2M/yr)
The majority of the capital cost would have to be spent below American Falls
Recharge spread over broader area, longer term improvement to reach gains/aquifer levels above and below Milner
20 years due to construction
A&B Conversion requires Minidoka enlargement and Salmon Flow Exchange to provide water supply
Partial conversion of District may be an option
$350M capital cost
Annual O&M at 1% of capital cost ($2.5M)
Also see costs under Minidoka Enlargement and Salmon Flow Exchange
Cost of partial conversion would be proportional.
Reduces pumping stress in a key location; long term improvement to reach gains/aquifer levels evenly distributed above and below American Falls
10 years
Costs are preliminary estimates for budget purposes only
Management Options Components Estimated Average Supply
(best information)Estimated Cost (best information)
Hydrologic Impacts Timeline for implementation
Other Hard Conversions (Hazelton Butte)
20 KAF (10,000 acres+/) Requires Salmon flow exchange and/or Minidoka for water supply
$20M capital cost
Annual O&M at 1% of capital cost ($200K)
Also see costs under Minidoka Enlargement and Salmon Flow Exchange
Improvements in reach gains below Milner, however results could be intermittent depending on surface supply
10 years
Soft Conversions requires Salmon flow exchange and/or Minidoka for water supply –
Full implementation requires salmon flow exchange
$23M capital cost
Assume annual O&M cost is borne by landowners
Long term improvements in reach gains above Milner, however results are not immediate and could be intermittent depending on surface supply
5 years
Demand Reduction
- dry year lease
- fallowing
- buy outs
- crop mix changes
160 KAF (have already achieved 40 KAF thru CREP)
$1,250/AF for acquisition of ground water rights
Other options should be less
Buy-outs would have a permanent impact to water budget through reduced depletions – other options depend on configuration of programs
2-10 years depending on options and amounts
Costs are preliminary estimates for budget purposes only
Weather Modification is a stand-alone option to be considered
independently of packagesOption Estimated Average
Supply (best information)Estimated Cost (best information)
Timeline for implementation
Weather Modification
60,000-190,000 AF/yr $250k-$700k/yr 1-to-2 years
Costs are preliminary estimates for budget purposes only
Weather Modification Feasibility Study Estimated Streamflow Increases
Management Alternative Packages
Packages Developed include:– Small (300 KAF); least expensive and
quickest to implement– Medium (600 KAF); more expensive and
takes more time to fully implement– Large (900 KAF); most expensive and will
take decades to fully implement– Demand Reduction and Recharge Emphasis
Hydrologic Goal – 600 kaf Change
– 600 kaf Water Budget Change
• Robust mix of conversions, aquifer recharge, demand reduction and conservation strategies
– Implementation Timeline – 20 years
– Cost – $600 million not including O&M
Phase I ActionsPhase I (1 – 10 years)
• Hydrologic target of 200kaf – 300kaf
• Initiate actions that increase aquifer levels, and spring and river flows
• Geographically distributed across the ESPA
• Build institutional confidence with long-term plan implementation
Phase I Actions
– Groundwater to Surface Water Conversions
– Managed Aquifer Recharge
– Demand Reduction • Buyouts, buy-downs and/or subordination agreements• Rotating fallowing, dry-year lease agreement, CREP• Crop mix modification • Surface water conservation
– Pilot Weather Modification Program
PLAN HYDROLOGIC TARGETS
Action Phase I Target (kaf) Long-Term Target (kaf)
Ground Water to Surface Water Conversion
100 100
Managed Aquifer Recharge 100 150-250
Demand Reduction 250-350
Surface Water Conservation 50
Crop Mix Modification 5
Rotating Fallowing, Dry-Year Lease Agreements and CREP Enhancements.
40
Buy Outs, Buy Downs, and/or Subordination Agreements
No Target (Opportunity-Based)
Weather Modification 50* No Target
TOTAL 200-300
600
CAMP Hydrologic Targets
* 50kaf based on conservative estimate from Upper Snake Weather Modification Feasibility study
Action Water Budget Change
Capitol Cost Ongoing Annual Cost
Cost per Acre-foot of benefit
Ground water-to-surface water conversions
100 KAF $30M (1) $300/AF
Recharge 100 KAF $15M $300K/yr equals $3M for years 1-10
$180/AF
Weather Modification 60 KAF– 190 KAF $700K/yr equals $7M for years 1-10
$50/AF
Surface Water Conservation in areas not impacting recharge to ESPA
50 KAF $20M (1) $400/AF
Crop Mix Modification 5 KAF $1M/yr equals $10M for years 1-10
$200/AF
Rotating fallowing, dry year leasing, CREP
40 KAF (2)
Program Administration and engineering
$5M over years 1-10
TOTALS 355 KAF – 485 KAF
$65M $25M over years 1-10
$227/AF
Notes :(1)It is assumed that the water users will take over annual O&M in these cases since these projects should reduce O&M costs from existing levels. (2) CREP has already achieved a 40 KAF water budget change so no additional costs are needed for this action unless CREP acreage decreases.
ESPA CAMP Phase 1 ACTIONS - COST PER ACRE FOOT OF BENEFIT
ESPA CAMP Hydrologic Analysis
A series of hydrologic analyses were conducted to determine the effects of the CAMP Phase 1 actions on aquifer levels and reach gains (spring flows) from the aquifer. The period of 1980-2005 was used as hydrologic input into the analysis. It was determined that over this time period, the Phase 1 CAMP actions could be achieved as follows:
Phase 1 CAMP Action Average acre-feet/year
Recharge (Snake River) 91,223
Recharge (Wood River) 22,565Conversions 85,027Surface Water Conservation 32,100Weather Modification 51,500Demand Reduction 44,835
TOTAL 327,250
ESPA CAMP Phase 1Estimated Increase in Reach Gains (Spring Flows) from the Aquifer at Selected Locations
Blackfoot to Neeley
0
20
40
60
80
100
120
140
May-80 May-85 May-90 May-95 May-00 May-05 May-10
cfs
Buhl to Thousand Springs
0
5
10
15
20
25
May-80 May-85 May-90 May-95 May-00 May-05 May-10
cfs
ESPA CAMP Phase 1Estimated Increase in Ground Water Levels at Selected Locations
Near American Falls Reservoir
0
0.5
1
1.5
2
May-80 May-85 May-90 May-95 May-00 May-05 May-10
feet
ESPA CAMP Phase 1 Funding Participation Targets
Water User Category Phase 1 Funding Participation Targets
Irrigated Agriculture$3 million annually (based on participation of $2 million annually for
ground water users and $1 million for surface water users)
Idaho Power$1 million - $1.5 million annually (for projects that qualify for
TEMP)*
Municipalities$700,000 annually (includes commitment to address rules and
statutes that may inhibit municipal growth)
Spring Users $200,000 annually (based of cfs)
Industrial and Commercial Users(not served by municipalities or ground water districts) $150,000 annually (based on estimated 15kaf use annually)
State of Idaho $3 million annually
FederalPursue federal grant and cost share funding opportunity; EQUIP,
Water for America, CREP and others
Recreation/Conservation Pursue grants and other funding opportunities
* Temperature Enhancement and Management Program
Select Additional Plan Components • Designed to enhance coordination, decision making and
aquifer management.• Environmental considerations, will seek to optimize
outcomes for fish and wildlife, recreation, hydropower, municipalities, irrigation, aquaculture and other uses.
• Clearinghouse, a flexible mechanism to connect willing participants.
• Outreach and Education, initial emphasis on local governments, domestic well owners and consumptive water users.
• Management Flexibility and Innovation, consider innovative strategies to solve water management problems.
Comprehensive Aquifer Management and Planning Program
• 2008 Legislation• House Bills No. 428 and 644• Created Aquifer Planning and Management
Program• Established Aquifer Planning and Management
Fund• New Idaho Code Sections: 42-1779
42-1780
Purpose
• Conduct statewide comprehensive aquifer planning and management effort over a 10-year period
• Avoid the Eastern Snake Plain conflicts in other areas of the state
• Develop management plans for selected basins with potential ground-surface water conflicts or other potential conflicts
Funding• 30 million dollar program to study and develop
Comprehensive Aquifer Plans for 10 Major Aquifers.• Legislature Appropriated $20 million in FY2009.• Appropriated $274,900 to IDWR for first year of
program• Interest from Fund will be routed back into Fund to
extend funding for duration of program• Governor Recommended using $12 million in FY2010
to offset General Fund Shortage.• Remaining $8 million will fund completion of
Rathdrum and Treasure Valley Aquifers and ESPA Monitoring through FY 2013.
Original Schedule of Work Based on $20 Million (plus interest)Basin FY 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018
ESPA Monitoring
Treasure Valley
Rathdrum Prairie
Palouse
Big Wood
Mountain Home
Bear
Teton
Big Lost
Portneuf
Blackfoot
Revised Schedule of Work Based on $8 Million (plus interest)
BasinFY 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018
ESPA Monitoring
Treasure Valley
Rathdrum Prairie
Comprehensive Aquifer Management and Planning
Ten
Priority
Aquifers
Anticipated Technical Studies
• Establish Monitoring Network • Develop Hydrologic Framework• Water Balance• Ground Water Model• Climate Change and Weather Modification
feasibility.• Storage Opportunities
Anticipated Planning Studies
• Water Demand Projections (50 year)• Facilitators have been hired for Rathdrum and
Treasure Valley.• Evaluate alternatives to meeting projected
demands:– Water Use Transfers (i.e., ag to DCMI)– Weather Modification Feasibility– Aquifer Recharge– New Storage – Inter-basin Transfers
Questions ?