methow valley irrigation district alternatives evaluation
DESCRIPTION
Methow Valley Irrigation District Alternatives Evaluation. Presented by Bob Montgomery, P.E. and David Rice, P.E. January 31, 2013. Alternatives Evaluation Report (AER) Scope. Coordination meetings Meetings with project team MVID board of directors and shareholders - PowerPoint PPT PresentationTRANSCRIPT
Methow Valley Irrigation DistrictAlternatives Evaluation
Presented byBob Montgomery, P.E. and David Rice, P.E.
January 31, 2013
Alternatives Evaluation Report (AER) Scope• Coordination meetings
– Meetings with project team– MVID board of directors and shareholders
• Hydrologic feasibility analysis– Groundwater well testing– Evaluation of individual well option
• Development of AER– Evaluation of 4 alternatives– Hydraulic analyses, cost analyses, concept
drawings– Draft and final reports
Groundwater Investigation
• Potential well sites identified• Test well drilling plan developed
– Description and specifications for drilling work• Test well drilling – 8 inch exploration wells
– MVID beaver pond property– Jumars property– Eileen property
Summary of Drilling at MVID Beaver Pond Property• Well drilled to 90 ft below ground surface
(bgs)• Static water level was 10 ft bgs• Encountered bedrock at 80 ft bgs• We are not recommending this site be
used for production wells
Summary of Drilling at Jumars Property
• Well drilled to 180 ft bgs• Static water level was 69 ft bgs• Good formations of sand and gravel were
found• Pump test not performed because of
freezing weather
Summary of Drilling at Eileen Property
• Well drilled to 156 ft bgs• Static water level was 8 ft bgs• Good formations of sand and gravel were
found• Higher withdrawals likely available at this
site• Pump test not yet performed
Summary of Alternatives
• Alternative 1– West canal replaced with pressurized pipe system– Supplied by pump station on Methow River
• Alternative 2– West canal replaced with pressurized pipe system– Supplied by wells in connection with Methow
River• Alternative 3
– West canal replaced with two pressurized pipe systems
– Supplied by wells in connection with Methow River
Summary of Alternatives (Cont.)
• Alternative 4– Convert to individual well systems, where
possible– Reduced West system – Upper West Side users
– Pressure pipe system– Supplied by well (or river pump station)– Users likely still within a reduced MVID
– Reduced East system – Lateral E1 replacement– Pressure pipe system– Supplied by well– System operated as part of a reduced MVID, or
through agreement with Town of Twisp
Alternative 1
Alternative 1 – Detailed Summary
• Supply– Methow River pump station
– 2.4 cfs (125 HP) pumping to users upstream– 8.6 cfs (200 HP) pumping to users
downstream• Pressurized PVC pipe system
– Main line – approx. 47,800 feet, 8” to 18” diam.– Laterals – approx. 29,600 feet, 3” to 8” diam.
• Storage (optional)– 132,000 gallons (upstream of pump station)– 476,000 gallons (downstream of pump station)
Alternative 1 – Implementation Costs
• Probable construction cost– $6 to $7 million (2013 dollars)
• Additional implementation costs– Land acquisition, engineering, permitting,
administrative
Alternative 1 – Life Cycle Costs
• Probable annual life cycle costs– Power: $30K to $35K (2013
dollars)– O&M: $140K to $160K (2013
dollars)– Replacement fund: $55K to $65K (2013
dollars)–Probable annual assessment
– $155 to $165 per acre for power + O&M– $50 to $60 per acre for replacement fund
– Analysis assumes– Okanogan PUD irrigation rate schedule– 3% annual inflation and 3% annual interest
Alternative 2
Alternative 2 – Detailed Summary
• Groundwater well supply– Total 11.0 cfs supply– Multiple large production wells
• Booster pump station– 2.4 cfs (75 HP) pump station to users upstream
of Roach Spill
Alternative 2 – Detailed Summary (Cont.)
• Pressurized PVC pipe system– Main line – approx. 47,800 feet, 8” to 18” diam.– Laterals – approx. 29,700 feet, 3” to 8” diam.
• Storage (optional)– 132,000 gallons (upstream of pump station)– 476,000 gallons (downstream of pump station)
Alternative 2 – Implementation Costs
• Probable construction cost– $6.5 to $7.5 million (2013 dollars)
• Additional implementation costs– Land acquisition, permitting, administrative
Alternative 2 – Life Cycle Costs
• Probable annual life cycle costs– Power: $40K to $45K (2013
dollars)– O&M: $145K to $165K (2013
dollars)– Replacement fund: $60K to $70K (2013
dollars)–Probable annual assessment
– $160 to $170 per acre for power + O&M– $50 to $60 per acre for replacement fund
– Analysis assumes– Okanogan PUD irrigation rate schedule– 3% annual inflation and 3% annual interest
Alternative 3
Alternative 3 – Detailed Summary
• Groundwater well supply– Upper middle system - total 5.1 cfs supply– Lower system - total 5.9 cfs supply– Multiple large production wells
• Booster pump station– 2.4 cfs (75 HP) pump station in upper/middle
system to users upstream of Roach spill
Alternative 3 – Detailed Summary (Cont.)
• Pressurized PVC pipe system– Main line – approx. 41,100 feet, 8” to 15” diam.– Laterals – approx. 29,700 feet, 3” to 8” diam.
• Storage (optional)– Upper/middle system
– 132,000 gallons (upstream of pump station)– 158,000 gallons (downstream of pump
station)– Lower system
– 317,000 gallons
Alternative 3 – Implementation Costs
• Probable construction cost– $5.5 to $6.5 million (2013 dollars)
• Additional implementation costs– Land acquisition, permitting, administrative
Alternative 3 – Life Cycle Costs
• Probable life cycle costs– Power: $40K to $45K (2013
dollars)– O&M: $145K to $165K (2013
dollars)– Replacement fund: $60K to $70K (2013
dollars)–Probable assessment
– $165 to $175 per acre for power + O&M– $50 to $60 per acre for replacement fund
– Analysis assumes– Okanogan PUD irrigation rate schedule– 3% annual inflation and 3% annual interest
Alternative 4
Alternative 4 – Detailed Summary• Combination of individual well systems
and pressurized pipe system where wells are not feasible
• Individual well systems– For parcels outside town of twisp – Groundwater likely available in valley and
margins in unconsolidated sediment formation– Recommend drilling deeper and using screens
for higher capacity wells
Alternative 4 – Detailed Summary• Reduced Upper West system
– Groundwater well supply – 2.5 cfs– Pressurized PVC pipe system
– Approx. 21,100 feet, 3” to 12” diam.– Storage (optional)
– 132,000 gallons
Alternative 4 – Detailed Summary (Cont.)
• Reduced Upper East System– Groundwater well supply – 2.5 cfs– Pressurized PVC pipe system
– Approx. 6,100 feet, 4” to 10” diam.– No storage– Operation
– Part of reduced MVID, or– Served through agreement with Town of
Twisp with separate irrigation meter
Alternative 4 – Implementation Costs
• Probable construction cost for reduced MVID system (Upper West and Upper East systems)– $2.1 to $2.6 million total (2013 dollars)
– $1.5 to $1.8 million for upper west (2013 dollars)
– $600K to $800K for upper east (2013 dollars)
• Additional implementation costs– Land acquisition, permitting, administrative
Alternative 4 – Life Cycle Costs
• Probable life cycle costs for reduced MVID (upper west and upper east systems)– Power: $12K to $16K (2013
dollars)– O&M: $20K to $30K (2013 dollars)– Replacement fund: $27K to $32K (2013
dollars)–Probable assessment
– $180 to $190 per acre for power + O&M– $120 to $130 per acre for replacement fund
– Analysis assumes– Okanogan PUD irrigation rate schedule– 3% annual inflation and 3% annual interest
Comparison of AlternativesFactor Alternativ
e 1Alternative 2 Alternative 3 Alternative 4
Capital Cost(funded by Ecology)
$6-7 million $6.5-7.5 million $5.5-6.5 million
$2.1-2.6 million
Annual Costs (power, O&M, replacement)
$225-260,000
$245-280,000 $245-280,000 $99-118,000
Estimated Annual Assessment (Power
+ O&M per acre)
$155-$165 $160-170 $165-$175 $180-$190
Additional Assessment for
Replacement Fund
$50-60 $50-$60 $50-$60 $120-$130
Water Supply River Pump Station
Groundwater Wells
Groundwater Wells
Groundwater Wells
Other Features Pressurized pipe
Two Zones
Pressurized pipe
Two Zones
Pressurized pipe
Two Systems, Two Zones in Upper System
Individual Well Systems,
MVID Reduced to Upper West and Upper East
Systems
Next Steps
• Completion of AER• MVID selection of preferred alternative• Selection criteria
– Cost (construction cost, land acquisition, O&M, replacement, impact to shareholder assessment)
– Water supply (impact to groundwater, surface water, and continuity with methow river)
– Property impacts– Social and political feasibility– Ease of permitting– Constructability, ease of operation
Questions and Comments
• To be collected at tables for each alternative
• For more information:– See www.mvid.org– Talk with MVID Directors and Staff– Visit the Trout Unlimited office in Twisp
(115 S. Glover St.) – Email questions and comments to: