Andy Selle. Dam Removal A Primer

Andy Selle Dam Removal A Primer

Dams in the United States ~ 2.5 million dams in the US ~ 99,000+ small dams (<10m) Death by a Thousand Cuts >700 dams have been removed in the US

Dams in United States 85% of Dams will be at their 50 YR design life in 2020 10000 7500 5000 <10 ft 10-24 ft 25-49 ft 50-99 ft 100+ ft 2500 0 1800 1810 1820 1830 1840 1850 1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 # Dams Built Year

Presentation Outline Dam Removal Economics Impoundment Sediment Stakeholder Involvement Alternatives and Cost Analysis Post Removal Restoration

Dam Removal Economics Repair vs. Removal Comparison Design and Construction Costs Property Values Recreational Economics

Estimated Removal Dam (removal date) Repair ($) Cost ($) % Less Lake Christopher Dam, CA (1994) 160,000 100,000 38% Edwards Dam, ME (1999) 9,000,000 2,100,000 77% Grist Mill Dam, ME (1998) 150,000 56,000 63% Sandstone Dam, MN (1995) 1,000,000 208,000 79% Two-Mile Dam, NM (1994) 4,100,000 3,200,000 22% Rat Lake Dam, WA (1989) 261,000 52,000 80% Waterworks Dam, WI (1998) 694,600 213,770 69% Mounds Dam, WI (1998) 3,300,000 500,000 85% Newport No.11 Dam, VT (1996) 783,000 550,000 30% Includes costs for repair or required fish passage Using low-end estimates for repair Removal is 60% less than Repair, on average Repair vs. Removal Cost

Estimate Costs Based on Project Complexity for: Feasibility -- Design -- Construction

Phase Range Mean n Feasibility $9,000 236,000 $106,000 30 Design $9,000-188,000 $88,000 11 Construction $6,500-720,000 $114,000 20 Mean total cost = $296,000 Source NOAA Fisheries, Dam removals in NE over last 10 years

Dam Removal Costs : Project Specific $30-60/CY for concrete demo and haul off $5-20,000 for dewatering $5-20/CY for excavation $100-$400 / LF for Active Channel Restoration

Cost by Height Based on 9 years of removals in PA Dam height (ft) Cost range Median Cost 1-3 $1,500 95,000 $17,200 4-6 5,000 300,000 38,500 7-9 3,200 187,000 45,651 10-15 50,000 195,000 70,000 16-25 30,000 440,000 117,000 Source: American Rivers

Property Values Provencher, B.; Sarakinos, H.; and Meyer, T. 2008. Does small dam removal affect local property values? An empirical analysis. Contemporary Economic Policy 26(2): 187-197. Lewis, L.; Bohlen, C.; and Wilson, S. 2008. Dams, dam removal, and river restoration: A hedonic property value analysis. Contemporary Economic Policy 26(2): 175-186. Properties near dams have lower value than similar properties further away Before dam removal, purchasers willing to pay $2,000 more to be at least ½-mile away from dam Following dam removal, purchasers willing to pay $134 more to be at least ½-mile away from former dam site No statistical impact of dam removal on resale values of waterfront properties relative to properties on intact impoundments

Having a hard time revitalizing your downtown? You may want to consider knocking the dam down. --Wall Street Journal, October 18, 2000

Recreational Value: Fishing Anglers spend $38 billion annually on fishing Trout Unlimited estimates $108 billion when the ripple effect is considered Removal restores connectivity, opening new habitat areas for

Recreational Value: Boating Canoeing/kayaking $100 million annual sales Kayaking is among fastest growing outdoor activities Finding free-flowing stretches is a challenge regional scarcity can increase economic value Kickapoo River, WI Following Ontario Dam removal (early 1990s) Non-local canoeists now spend $1.2 million per year on boat rentals, lodging, gas, and other items in economically depressed area Baraboo River, WI After 3 recent dam removals near downtown Baraboo: New business is supplying 70-80 boat shuttles per weekend day in summer

Impoundment Sediment Estimate the pre-dam surface using DOR and survey Perform temporary drawdown if possible Divide sediment volume into mobile and immobile portions Perform Due Diligence on Contamination

Source: Doyle et al. 2003

Parameter Screening Benchmarks Dam Impoundment Dstrm Ustrm Impoundment Samples Sample Sample Sample Statistics (Important: Units listed by category below) MCP S1 / GW1 TEC PEC TEL PEL S1 S2 S3 S4 S5 Min Max Mean Human Health Freshwater (1) Marine (2) Metals [mg/kg] Antimony 20.0 NC NC 0 0 Arsenic 20.0 9.8 33.0 7.2 41.6 2.465 2.465 8.5 2.465 2.465 2.5 8.5 4.5 Cadmium 2.0 1.0 5.0 0.7 4.2 0.4935 0.4935 2.8 0.4935 0.4935 0.5 2.8 1.3 Chromium (TOTAL) 30.0 43.4 111.0 52.3 160.4 2.465 2.465 235 2.465 2.465 2.5 235.0 80.0 Copper NC 31.6 149.0 18.7 108.2 2.465 2.465 286 2.465 2.465 2.5 286.0 97.0 Lead 300.0 35.8 128.0 30.2 112.2 2.465 2.465 88.4 2.465 2.465 2.5 88.4 31.1 Mercury 20.0 0.2 1.1 0.1 0.7 0.05 0.05 2.4 0.05 0.05 0.1 2.4 0.8 Nickel 20.0 22.7 48.6 15.9 42.8 2.465 2.465 28.4 2.465 2.465 2.5 28.4 11.1 Silver 100.0 NC NC 0.7 1.8 4.9 4.9 98.7 4.9 4.9 4.9 98.7 36.2 Zinc 2,500.0 121.0 459.0 124.0 271.0 2.465 2.465 227 2.465 2.465 2.5 227.0 77.3 SVOCs (PAHs)[ug/kg] Total PAHs 1,610.0 22,800.0 1,684.1 16,770.4 1100 667 1100 1100 1100 Pesticides (ug/kg) 0 0 2,4'-DDT NC NC NC BDL BDL BDL BDL BDL 0 0 4,4'-DDT 3,000.0 NC NC 1.2 4.8 BDL BDL BDL BDL BDL 0 0 Sum DDT 4.2 62.9 BDL BDL BDL BDL BDL 0 0 Total DDTs 5.3 572.0 3.9 51.7 BDL BDL BDL BDL BDL 0 0 PCBs (ug/kg) 0 0 Total PCBs 2,000.0 59.8 676.0 21.6 188.8 BDL BDL BDL BDL BDL 0 0 VOCs (mg/kg) 0 0 Methyl tert-butyl ether (MTBE) 0.1 NC NC BDL BDL BDL BDL BDL 0 0 Benzene 2.0 NC NC BDL BDL BDL BDL BDL 0 0 Toluene 40.0 4.5 4.5 BDL BDL BDL BDL BDL 0 0 Physical Characterisitcs Total Organic Carbon (mg/kg Dry Weight) 7970 5760 13400 BDL 237000 Percent Water (%) Grain Size Distribution % Gravel 2.6 4.7 13.9 5.8 7 % Sand 95.3 94.4 85.4 91.4 90.36 % Clay 2.1 0.9 0.7 2.9 2.64

Stakeholder Involvement Occurs in the Feasibility Stage Real Information is Critical Visual Concepts Focus Group Discussions

Design overview Performance criteria Improve fish habitat Restore stream Patient access No increase in flooding

Existing Conditions

Proposed Conditions

Alternatives and Cost Analysis Repair Partial Removal Full Removal Full Removal Active Restoration Full Removal Passive Restoration Repair and Fishway

Post-Removal Restoration 2 Paths to the Same End = Restored Channel Active Restoration accelerates the process of channel and habitat formation BUT adds anywhere from $100-$400 / LF of restored channel Passive Restoration allows the stream to restore itself, a much cheaper option BUT can take decades or centuries to complete

Active Restoration

Upper Mill Creek 1998 Headwaters Flow

After 3 years

Passive Restoration

Which Approach? Active vs. Passive Channel Recovery ACTIVE PASSIVE Impoundment Mat l: Cohesive Non-cohesive Sediment Quantity Full Impoundment Channel Maintained Sediment Quality Contaminated Clean Impoundment Width Bankfull Width >>10 <10 Budget Substantial Tight / Fixed T & E Species Present Absent Downstream Channel Condition Intact Degraded

Summary Understand Site Complexity Plan a Budget Accordingly Complete Due Diligence on Impoundment Sediment Identify and Understand Unique Site Design Challenges Understand Post-removal Restoration Options Provide Tangible, Factual Information to Stakeholders

Economic Implications Active vs. Passive Channel Recovery Active Recovery Estimate Item Unit Unit Cost Quantity Total Cost Dam Demolition LS $20,000 1 $20,000 Channel Design LS $150,000 1 $150,000 Excavation CY $15 10,000 $150,000 Channel Construction LF $100 3000 $300,000 Seeding and Tree Planting ACRE $4,000 50 $200,000 Invasive Control ACRE $500 50 $25,000 Grand Total: $845,000 Passive Recovery Estimate Item Unit Unit Cost Quantity Total Cost Dam Demolition LS $20,000 1 $20,000 Seeding and Tree Planting ACRE $4,000 50 $200,000 ***Active Recovery approximately 2-4X cost of Passive Recovery*** Invasive Control ACRE $500 50 $25,000 Grand Total: $245,000