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Home My WebLink AboutRWSA Water Supply Proj 4-20-99Draft Rivanna Water and Sewer Authority Preliminary Alternatives ~ [] U Public Information Meeting April 20, 1999 Rfver Resen~r RIVANNA WATER SEWER AUTHORITY PRELIMINARY WATER SUPPLY ALTERNATIVES Increase in Estimated Unit Cost Alternative 2050 Cost ($) (S/gallon) Safe Yield (mgd) IDredge South Fork Rivanna River Reservoir 10 112,000,000 11.20/gallon Decrease Sediment Load into South Fork To be Rivanna River Reservoir Determined Revise Downstream Release Regime at South Fork Rivanna River Reservoir 3.8 386,000 0.12/gallon Add 4 ft. Crest Controls on South Fork Rivanna Dam 6 4,300,000 0.72/gallon Add 8 ft. Crest Controls on South Fork Rivanna Dam 11 14,700,000 1.34/gallon Utilize South Fork Rivanna River Reservoir as Pumped Storage Reservoir 0 15 ft. Draw Down of Chris Greene Lake 3 7,400,000 2:47/gallon 20 ft. Draw Down of Chris Greene Lake 5.5 14,000,000 2.54/gallon Utilize Chris Greene Lake as a Pumped Storage Reservoir 0 I Dredge Sugar Hollow Reservoir 0.1 7,400,000 74/gallon Pumpback to South Fork ' Rivanna River Reservoir 15 56,000,000 3.73/gallon Comments \\Wiiiva~Projects\30502\SheetsLMternative Comn~nts 3\ Sheetl 4/12/99 @ 9:15 AM RIVANNA WATER SEWER AUTHORITY PRELIMINARY WATER SUPPLY ALTERNATIVES ' Reduction Estimated Unit Cost Alternative in Cost ($) (S/gallon) Demand (mgd) Water Conservation --Plumbing Fixture 1.5 0 --Comm./Industrial 0.08 --Education 0.17 2,500,000 Drought Management Demand Side 2.4 Drought Management Supply Side 1 Leak Detection and Meter Calibration N/A Growth Management 1.7 Comments Increase in Estimated Unit Cost Alternative Demand Cost ($) (S/gallon) (m~d) Regional Cooperation 3 ~\Willva~rojects\30502\Sheets~Alternative Comments 3\Sheet 2 4/12/99 @ 9:15 AM RIVANNA WATER SEWER AUTHORITY PRELIMINARY WATER SUPPLY ALTERNATIVES Increase in Estimated Unit Cost Alternative Safe Yield (mgd)i Cost ($) (S/gallon) Aquifer Storage & Recovery 0 N/A N/A Conventional Withdrawal of Groundwater 0.1 1,200,000 12/gallon James River Withdrawal at Scottsville 15 72,000,000 4.80/gallon Rivanna River Withdrawal 4.7 17,800,000 3.79/gallon Mechums River Withdrawal 0.2 850,000 4.25/gallon Mechums River Withdraw. + Conversion of Ragged Mtn. to Pumped Storage Reservoir 10 47,000,000 4.70/gallon Construct Dam on Buck Mountain Creek 14.4 57,000,000 3.96/gallon Construct Dam on North Fork Rivanna River 15.4 79,000,000 5.13/gallon Construct Dam on Preddy Creek 6.4 91,000,000 14.22/gallon Construct Dam on Mechums River Near Lake Albemarle 13.3 68,000,000 5.1 l/gallon Construct Dam on Mechums River Near Midway 5.6 26,000,000 4.64/gallon Construct Dam on Buck Island Creek 1'5 118,000,000 7.87/gallon Construct Dam on Moormans River 11.6 106,000,000 9.14/gallon No Action 0 Comments \\Willva~Projects~30502~Sheets~Altemative Comments 3\Sheet 3 4/12/99 @ 9:15 AM RIVANNA WATER SEWER AUTHORITY PRELIMINARY WATER SUPPLY ALTERNATIVES MATRIX INCREASE IN ESTIMATED UNIT COST POTENTIAL # OF POTENTIAL IMPACTS TO PREVIOUSLY PREVIOUSLY APPROXIMATE ALTERNATIVE Z0so SAFE YIELD COST ($) (S/g) RESIDENTIAL IDENTIFIED CULTURAL RESOURCES IDENTIFIED T & E WETLAND IMPACTS (mgd) DISPLACEMENTS STRUCTURES ARCHAEOLOGICAL SPECIES in vicinity (Acres) Dredge South Fork Rivanna River Reservoir I0 112,000,000 $! 1.20/gallon 0 0 0 5 Decrease Sediment Load into South Fork To ~ Rivanna River Reservoir Determined Revise Downstream Release Regime at South Fork Rivanna River Reservoir 3.8 386,000 $0.12/gallon 0 0 0 0 Add 4 ft. Crest Controls on South Fork Rivanna Dam 6 4,300,000 $0.72/gallon 2 I I James Spiny Mussel 18 Add 8 ft. Crest Controls on South Fork Rivanna Dam I 1 14,700,000 $1.34/gallon 2 I I .lames Spiny Mussel 39 Utilize South Fork Rivanna River Reservoir as a Pumped Storage Reservoir 0 0 0 0 minimal 5 ft. Drawdown of Chris Greene Lake 3 7,400,000 $2.47/gallon 0 0 0 minimal 20 ft. Draw Down of Chris Greene Lake 5.5 14,000,000 $2.54/gallon 0 0 0 minimal Utilize Chris Greene Lake as a Pumped Storage Reservoir 0 0 0 0 minimal Dredge Sugar Hollow Reservoir o. 1 7,400,000 $74/gallon 0 0 0 2 Pumpback to South Fork Rivanna River Reservoir 15 56,000,000 $3.73/galion 0 0 0 James Spiny Mussel 2 \\WlLLVA\PROdECTS\30502\SHEETS\3AIternmatrix\Sheetl 4/12/99 @ 9:15 AM RIVANNA WATER SEWER AUTHORITY PRELIMINARY WATER SUPPLY ALTERNATIVES MATRIX REDUCTION ESTIMATED UNIT COST POTENTIAL # OF POTENTIAL IMPACTS TO PREVIOUSLY PREVIOUSLY APPROXIMATE ALTERNATIVE IN COST ($) (S/g) RESIDENTIAL IDENTIFIED CULTURAL RESOURCES IDENTIFIED T & E WETLAND IMPACTS DEMAND (mgd) DISPLACEMENTS STRUCTURES ARCHAEOLOGICAL SPECIES in vicinity (Acres) Water Conservation --Plumbing Fixture 1.5 0 0 0 0 0 --Comm./Industrial 0~08 --Education o. 17 2,500,000 Drought Management Demand Side 2.4 0 0 0 0 Drought Management Supply Side I 0 0 0 0 Leak Detection and Meter Calibration Not applicable 0 0 0 0 Growth Management 1.7 INCREASE ESTIMATED UNIT COST POTENTIAL # OF POTENTIAL IMPACTS TO PREVIOUSLY PREVIOUSLY APPRoxIMATE ALTERNATIVE IN COST ($) (S/g) RESIDENTIAL IDENTIFIED CULTURAL RESOURCES IDENTIFIED T & E WETLAND IMPACTS DEM, AND (mgd) DISPLACEMENTS STRUCTURES ARCHAEOLOGICAL SPECIES in vicinity (Acres) Regional Cooperation 3 \\WlLLVA\PROJECTS\30502\SHEETS\3AIternmatrix\Sheetl (2) 4/12/99 @ 9:15 AM RIVANNA WATER SEWER AUTHORITY PRELIMINARY WATER SUPPLY ALTERNATIVES MATRIX INCREASE IN ESTIMATED UNIT COST POTENTIAL # OF POTENTIAL IMPACTS TO PREVIOUSLY PREVIOUSLY APPROXIMATE ALTERNATIVE 20so SAFE YIELD COST ($) (S/gallon) RESIDENTIAL IDENTIFIED CULTURAL RESOURCES IDENTIFIED T & E WETLAND IMPACTS (mgd) DISPLACEMENTS STRUCTURES ARCHAEOLOGICAL SPECIES in vicinity. (Acres) Aquifer Storage & Recovery 0 Not applicable Not applicable Conventional Withdrawal of Groundwater o. I 1,200,000 $12/gallon 0 0 0 minimal lames River Withdrawal at Scottsville 15 72,000,000 $4.80/gallon 0 I I 5 Rivanna River ~ithdrawal 4.7 17,800,000 $3.79/gallon 0 0 0 2 Mechums River Withdrawal 0.2 850,000 $4.25/gallon 0 0 0 minimal Mechums River Withdraw. + Conversion of Ragged Mtn. to Pumped Storal~e Reservoir 10 47,000,000 $4.70/gallon I 0 0 5 Construct Dam on Buck Mountain Creek 14.4 57,000,000 $3.96/gallon I 6 0 James Spiny Mussel 59 Construct Dam on North Fork Rivanna River 15.4 79,000,000 $5.13/gallon 2 3 4 72 Construct Dam on Preddy Creek 6.4 9 I,OOO,OOO $14.22/gallon 6 7 0 77 Construct Dam on Mechums River Near Lake Albemarle 13.3 68,000,000 $5. I I/gallon 21 18 I James Spiny Mussel 107 Construct Dam on Mechums River Near Midway 5.6 26,000,000 $4.64/gallon 6 7 0 James Spiny Mussel 52 Construct Dam on Buck Island Creek 15 118,000,000 $7.87/gallon 14 6 0 103 Construct Dam on Moormans River II .6 106,000,000 $9.14/gallon 22 14 I 68 No Action 0 0 0 0 0 \\WlLLVA\PROJECTS\30502\SHEETS\3AIternmatrix\Sheetl (3) 4/12/99 @ 9:15 AM Assumptions All pricing is in current dollars (January 1999) Costs are based on an "order of magnitude" estimate Cost for property acquisition based on $11,000/acre ($8,000/acre for wetland mitigation) Cost estimates include: 15% engineering/legal/administrative fees 20% contingency Costs for water distribution system improvements are not included Transportation costs are not included except where noted otherwise Wetland mitigation costs are included in the cost estimate and are based on approximate wetland impacts Cost estimates do not- include costs associated with mitigation for threatened/endangered species and cultural resources 7QlO or 30% mean annual flow is adequate to meet agency requirements Pipeline alignments are conceptual and for cost estimating purposes only Peaking factor of 1.5 used to size the waterworks facilities where appropriate Operation and maintenance costs not included 8 wiliva\ 30502ho.p65 Dredging South Fork Rivanna River Reservoir Dredging of bottom sediments in the middle and upper reaches of the reservoir approximately three times through 2050, each time returning the reservoir to it's original storage capacity Requires dewatering and disposal of dredged spoil. Includes 3 mgd expansion of South Fork Rivanna water treatment plant, raw and finished water pump stations.. · Increase in 2050 safe yield- 10 million gallons.per day · Estimated cost- $112 million through 2050 · Locating suitable sites for dredge spoil dispOsal poses challenge · Approximately 100 acres of land needed Per'dredging event · Temporary water quality impacts · Direct impact to 5 acres of wetlands; additional impacts to shallow water habitat · No anticipated impacts to cultural resources and threatened/endangered species · No residential displacements 9 willv~\ 30502ho p65 Decrease Sediment Load into South Fork Rivanna River Reservoir Implementation of watershedprotection measures within the South Fork Rivanna River Reservoir watershed which encompasses over 260 square miles. May include construction of regional stormwater management ponds on target watersheds, the effects of a new Water Protection Ordinance adopted in 1998, and possible expansion of stream buffer requirments. · Increase in 2050 safe yield for regional stormwater management ponds alone- million gallons per day · Increase in 2050 safe yield for ordinance alone- __ million gallons per day · Increase in 2050 safe yield for both regional ponds and expansion of stream buffer requirements- million gallons per day · Estimated cost- $ million for regional ponds · Estimated cost for implementation and expansion of stream buffer requirements- $ · Target sites suitable for regional stormwater management ponds · Environmental benefits to water quality · Approximately acres of wetland impacts for regional ponds · May require surveys for threatened/endangered species and cultural resources · Assumed approximately 50% sediment removal efficiency for regional ponds based on preliminary results of Lickinghole Creek basin monitoring 10 willva\ 30502ho.;:~65 Decrease Sediment Load into South Fork Rivanna River Reservoir (continued...) Assumed % removal of sediment load for watershed protection measures implemented as a result of the watershed protection ordinance No anticipated residential displacements · Impacts to private property in the form of reduced agricultural land 11 willva\ 30502ho.o65 Revise Downstream Release Regime at South Fork Rivanna River Reservoir Presently, the release regime at South Fork Rivanna River Reservoir would consist of augmenting natural streamflows during severe drought conditions. The revised release scenario would be operated such that the natural stream- flow would not be augmented during severe drought conditions. Includes installation of stream gages on major reservoir tributaries as well as controls/ valves on the existing dam. · Increase in 2050 safe yield- 3.8 million gallons per day · Estimated cost- $ 386,000 · Minimal environmental impacts over long term · Downstream habitat assessment may be required · No anticipated impacts to cultural resources and threatened/endangered species · No residential displacements 12 willva\ 30502ho.p65 4' Crest Controls on South Fork Rivanna Dam Addition of four-foot crest controls to increase the normal pool elevation from 382 feet to 386 feet. Requires replacement of Route 676 bridge over Ivy Creek and acquisition of land around the reservoir. Assumed no discharge of fill mate- rial into jurisdictional areas and therefore no requirements for wetland mitiga- tion. · Increase in 2050 safe yield- 6 million gallons per day · Estimated cost- $4.3 million · Increases useable storage volume by 600 million gallons · Increase in storage volume reduces rate of system storage loss over time · Purchase of approximately 70 acres of land surrounding reservoir · Requires alteration to existing FERC license exemption · Approximately J8 acres of wetlands inundated by new pool · James Spiny Mussel previously identified in vicinity; would need to examine potential impacts · Possible impact to one previously identified archaeological site (eligibility not' determined); additional archaeological surveys may be required · Potential indirect impact to one previously identified historic structure (eligibility not deter- mined); additional architectural surveys may be required · Possible displacement of 2 residences · Possible impacts to private property around reservoir such as docks, boat houses, etc. 13 willva\ 30502ho.p65 8' Crest Controls on South Fork Rivanna Dam Addition of eight-foot crest controls to increase the normal pool elevation from 382feet to 390feet. Requires replacement of Route 676 bridge over Ivy Creek and acquisition of land around the reservoir. Includes 4.5 mgd expansion of South Fork Rivanna Reservoir intake, plant and pump stations. Assumed no discharge of fill material into jurisdictional areas and therefore no require- ments for wetland mitigation. · Increase in 2050 safe yield- ! 1 million gallons per day · Estimated cost- $14.7 million · Increases useable storage volume by 1,300 million gallons · Increase in storage volume reduces rate of system storage loss over time · Purchase of approximately 170 acres of land surrounding reservoir · Requires alteration to existing FERC license exemption · Approximately 39 acres of wetlands inundated by new pool · James Spiny Mussel previously identified in vicinity; potential effects undetermined · Possible impact to one previously identified archaeological site (eligibility not determined); additional archaeological surveys may be required · Potential indirect impact to one previously identified historic structure (eligibility not determined); additional architectural surveys may be required · Possible displacement of 2 residences · Possible impacts to private property around reservoir such as docks, boat houses, etc. 14 willva\ 30502ho.p65 South Fork Rivanna River Reservoir as Pumped Storage Reservoir High flow skimming from the Rivanna River into the South Fork Rivanna River Reservoir. Includes a new pump station and new intake on the Rivanna River just downstream of the confluence of the North and South Forks of the Rivanna River. The drainage area of the Rivanna River at the intake is approximately 450 square miles. No withdrawal to occur when flow in the Rivanna River drops below 30% of mean annual flow. · Increase in 2050 safe yield- 0 million gallOns per day Insufficient flow exists in Rivanna River when South Fork Rivanna River Reservoir has available volume to refill · No storage available in reservoir during non-drought conditions · Sedimentation into reservoir results in continued reduction in available storage · Minimal wetland impacts · No anticipated impacts to cultural resources and threatened/endangered species · No residential displacements 15 willva\ 30502ho.p65 5' Drawdown of Chris Greene Lake to Supplement North Fork Rivanna River Convey water from Chris Greene Lake to the North Fork Rivanna water treat- ment plant during severe drought conditions to supplement the North Fork Rivanna River water system. Would be limited to a 5-foot drop of pool elevation. Includes a 3.2 mgd expansion of the North Fork Rivanna finished water pump station and water treatment plant. Chris Greene Lake is a 52-acre impoundment with storage volume of 334 million gallons. · Increase in 2050 safe yield- 3 million gallons per day · Estimated cost- $7.4 million · Would require coordination to address prior use of Land and Water Conservation Funds · Currently designated a water supply protection area · Currently used for swimming, fishing and boating · Frequency of occurrence: approximately once every decade · Possible impacts to existing recreational activities during drawdown · Anticipate minimal environmental impacts · No anticipated impacts to cultural resources and threatened/endangered species · No residential displacements 16 w~i;va\ 30502ho,D65 20' Drawdown of Chris Greene Lake to Supplement North Fork Rivanna River Convey water from Chris Greene Lake to the North Fork Rivanna water treat- ment plant during severe drought conditions to supplement the North Fork Rivanna River water system. Would allow for a maximum drawdown of 2O feet. Includes a 7.2 mgd expansion of the North Fork Rivanna finished water pump station and water treatment plant. · Increase in 2050 safe yield- 5.5 million gallons per day · Estimated cost- $14 million · Would require coordination to address prior use of Land and Water Conservation Funds · Greater drawdown could have significant recreational impacts · Potential impacts to fish populations · No anticipated impacts to cultural resources and threatened/endangered species · No residential displacements 17 wiiiva\ 30502ho 365 Use Chris Greene Lake as Pumped Storage Reservoir High Jlow skimming from the North Fork Rivanna River into Chris Greene Lake via a river intake and pump station. During drought conditions, raw water would be conveyed from Chris Greene Lake to the North Fork Rivanna water treatment plant. No skimming to occur when flow in the Rivanna River drops below 30% of mean annual flow. · Increase in 2050 safe yield- 0 million gallons per day · Insufficient flow in North Fork Rivanna River when Chris Greene Lake has available volume to refill · No available storage in reservoir during non-drought conditions · Minimal wetland impacts · No anticipated impacts to cultural resources and threatened/endangered species · No residential displacements 18 willva\ 30502ho.p65 Dredge Sugar Hollow Reservoir Dredging of landslide debris and bottom sediments in the reservoir once through 2050. Requires disposal of dredge spoil but minimal dewatering. During drought conditions, the additional volume would be released to the South Fork Reservoir or diverted to the Ragged Mountain Reservoirs. · Increase in 2050 safe yield- 0.1 million gallons per day · Estimated cost- $7.4 million · Locating suitable sites for dredge spoil disposal poses challenge due to topography · Approximately 25 acres of land needed for disposal · Temporary water quality impacts · Direct impact to 2 acres of wetlands; minimal impacts to shallow water habitat · No anticipated impacts to cultural resources and threatened/endangered species · No residential displacements 19 willva\ 30502h0,~65 Pumpback to South Fork Rivanna River Reservoir (Indirect Re. Use) Pumpback of treated effluent from the Moore's Creek waste water treatment plant to the Mechums River to augment flow into the South Fork Rivanna River Reservoir. Includes a 10. 5 mgd expansion of the S. Fork Rivanna River Reservoir pump stations and water treatment plant, a new 22.5 mgd pump station at Moore's Creek, new filters at the Moore's Creek treatment plant, a new 22.5 mgd boosterpump station, and a new 36-inch pipeline along 1-64 for a distance of approximately 12.5 miles. · Increase in 2050 safe yield - 15 million gallons per day · Estimated cost - $56 million · Will require the acquisition of land along the pipeline corridor · Anticipate close scrutiny byVirginia Dept. of Health · Approximately 2 acres of wetland impact · James Spiny Mussel previously identified in the vicinity; would need to examine potential ~mpacts · Impacts to cultUral resources not known; additional surveys may be required · No anticipated residential displacements 20 wiltva\ 30502ho,D65 Water Conservation DeveloRment and implementation of a long term water conservation program consisting of plumbing fixture changeout (without retrofit program), public education / awareness programs. Short term savings resulting from outdoor watering restrictions and mandatory conservation are addressed under drought management. · Reduction in Demand - 1.5 mgd (Residential) due to plumbing fixture changes through the year 2050 · Reduction in Demand - 0.08 mgd (Commercial and Industrial) · Reduction in Demand - 0.1'7 mgd (Residential) due to water conservation public awareness and education · Cost of plumbing F~xture changeout - $0 · Cost ot5 Public Education/Awareness program - $50K per year ($2.5 million through 2050) · No major permanent restrictions on outdoor water use assumed · Savings estimates based on the following assumptions: Fixture Type Current Type Assumed Use Toilet 3.5 gallons 1.6 gallons per flush per flush Showerhead 5.0 gallons 2.5 gallons per minute per minute 21 willva\ 30502ho.p65 Drought Management Development and implementation of a drought management plan. Plan in- cludes mandatory water conservation and a ban on outdoor water use. Plan also includes a drought management operating scenario for the RWSA existing water supply facilities. Supply side techniques include synergistic operation of existing facilities, reduction or elimination of downstream releases, and diver- sion from other uses. 1.8 mgd reduction in demand due to mandatory water conservation and limitations on outdoor water use during summer drought · Indoor water consumption reduced by 5% · Outdoor water consumption reduced by 25% 0.6 mgd reduction in demand for similar restrictions during winter drought · I mgd increase in safe yield due to system wide drought management 22 willva\ 30502ho.p65 Leak Detection and Meter Calibration Leak Detection and Meter Calibration programs are implemented by the Albemarle County Service Authority (ACSA) and the City of Charlottesville as the distributors of finished water to the end user. Both currently have active leak detection and meter calibration efforts underway. · No specific reduction in demand can be directly attributed to this alternative · Financial incentive exists for leak detection · Meter calibration and changeout is revenue neutral · Overall documented system losses indicate that entire system is operating within generally accepted limits · Leaks are detected and responded to early using billing monitoring and written notification system · Meter.change out is being done systematically by both the ACSA and City · Meter calibration results from1998 indicate acceptable meter performance 23 witlva',. 30502ho.p65 Growth Management Attempt to slow population growth in the Albemarle County portion of the Urban Service Area to reduce future demand for public water supply. Potential means include further restricting the size of Urban Service Area, increasing minimum lot sizes, and actively discouraging industrial, commercial, or business development within the Urban Service Area. · Could decrease 2050 demand by as much as 1.5 million gallons per day · Costs would be significant but cannot reasonably be quantified Reducing population growth within the Urban Service Area would likely result in increased growth in surrounding rural areas on well and septic systems May be politically infeasible as it reverses Comprehensive Plan and policy of two decades attempting to guide growth into Urban Service Area and away from rural areas Secondary impacts would include dispersed development outside the Urban Service Area, requiring construction and maintenance of infrastructure improvements to roads and utilities · Transportation and safety impacts could be expected 24 willva\ 30502ho.p65 Regional Cooperation Interconnection &etween the Rivanna Water and Sewer Authority water supply system and the Rapidan Service Authority system in order to provide additional water supply to the Rapidan Service Authority. The Rapidan Service Authority projects additional demand for approximately 2. 0 to 3.0 mgd of water through the year 2050. Connection would be via pipeline approximately 3.5 miles long at the closest approach of the two service areas, along US. Route 29 south of Ruckersville. Increase in 2050 demand- 3 million gallons per day Estimated cost- $ The Rapidan Service Authority is considering a variety of short term and long term solutions to their future water needs Potential environmental impacts not yet determined 25 willva\ 30502ho. D65 Aquifer Storage and Recovery Storage of treated water in a suitable aquifer during times when available wa- ter supply exceeds demand and subsequent recovery of water during drought conditions. Increase m 2050 safe yield - 0 million gallons per day Unsuitable geologic conditions: presence of subsurface rock with low transmissivity · Not feasible 26 willva\ 30502ho.p65 Conventional Withdrawal of Groundwater Installation of 15 shallow groundwater wells and piping water to the existing South Fork and North Fork water treatment plants (WTP): 6 wells in the vicinity of North Fork WTP and 9 wells in the vicinity of South Fork WTP. Includes instal- lation of wells, pump, piping and land acquisition. Groundwater is typically of good quality but has the potential for high iron. Increase in 2050 safe yield - 0.1 million gallons per day Estimated cost- $1.2 million Minimal environmental impacts No residential displacements are anticipated 27 willva\ 30502ho.p65 James River Withdrawal at Scottsville Withdrawal of water from the James River at Scottsville with a new 22. 5 mgd river intake, raw waterpump station, a new 36-inch pipeline to the South Fork water treatmentplant, and a 10.5 mgd expansion of the South Fork Rivanna water treatment plant and finished water pump station. Alternatively, an option was considered which included a new 22. 5 mgd river intake, raw and finished water pump stations, and a new water treatment plant at Scottsville with 36- inch pipeline along Route 20 to Charlottesville. The costs were essentially equiva- lent. The option presented provides water treatment at the South Fork Plant. · Increase in 2050 safe yield - 15 million gallons per day · Estimated cost - $72 million · Requires acquisition of a 25' wide easement along entire pipeline length · Approximately 5 acres of wetland impacts · Impacts to threatened/endangered species not known; additional surveys may be required Potential impact to archaeological resources along James River; additional archaeological surveys may be required Potential impact to previously identified Scottsville Historic District; additional surveys related to historic structures may be required · No anticipated residential displacements 28 w~¥a\ 30502ho.~65 Rivanna River Withdrawal Withdrawal of water from the Rivanna River near Glenmore Country Club. Includes a new 7 mgd river intake, raw and finished water pump station, water treatment plant, booster pump station, and a new 24-inch/16-inch pipeline from the finished water pump to the existing 16-inch main along Route 250 which currently serves the Village of Rivanna. · Increase in 2050 safe yield - 4.7 million gallons per day · Estimated cost - $17.8 million · Potential water quality concerns · Moore's Creek waste water treatment plant discharge is located more than 5 miles upstream · Requires acquisition of a 25' wide easement along entire pipeline length · Approximately 2 acres of wetland impacts · Impacts to threatened/endangered species not known; additional surveys may be required · Impacts to cultural resources not known; additional survey for cultural resources may be required · No anticipated residential displacements 29 willva", 30502ho.p65 Mechums River Withdrawal Skimming of high flows from the Mechums River at the site of the abandoned intake and pump station near Lake Albemarle and pump to the Ragged Mountain Reservoirs. Includes rehabilitation of the river intake, pump station and ancillary features, as well as access road improvements. · Increase in 2050 safe yield - 0.2 million gallons per day · Estimated cost - $850,000 · Insufficient flows in Mechums River during severe drought conditions · Useful only when there are droughts in two successive years · Minimal impacts to wetlands · Impacts to cultural resources or threatened/endangered species not known; additional surveys may be required · No anticipated residential displacements 30 willva\ 30502ho. D65 Mechums River Withdrawal and Conversion of Ragged Mountain to Pumped Storage Reservoir Skimming of high flows from the Mechums River into Ragged Mountain Reser- voirs by rehabilitating and expanding the abandoned intake and pump station on the Mechums River to 10 mgd. This option is combined with raising the dam for Lower Ragged Mountain Reservoir by 50' creating'a normal pool elevation of 700' with a surface area of 275 acres and storage capacity of 2,800 million gallons. Results in inundation of existing dams. Option also includes new 24- inch pipeline, 15 mgd intake on Ragged Mountains, and 8 mgd expansion of Observatory water treatment plant and pump station. · Increase in 2050 safe yield - 10 million gallons per day · Estimated cost - $47 million · Requires purchase of approximately 125 acres of additional land Approximately 5 acres of wetlands inundated by increased pool elevation at Ragged Moun- tain Reservoirs Impacts to cultural resources or threatened/endangered species not known; additional surveys may be required · One potential residential displacement 31 w:llv;l\ 30502ho a65 Construct Dam and Reservoir on Buck Mountain Creek Construction of a dam and reservoir on Buck Mountain Creek 1.5 miles up- stream of the confluence of Buck Mountain Creek and the S. Fork Rivanna Reser- voir. Includes: new 21.6 mgd intake, 9. 6 mgd expansion of the existing S. Fork Rivanna intake, raw water pump station, water treatment plant and finished water pump station. Normal pool elevation of the new reservoir 480feet with surface area of 670 acres and storage capacity of 5,242 million gallons. Drain- age area of reservoir 38 square miles. · Increase in 2050 safe yield - 14.4 million gallons per day · Estimated Cost - $57 million · Assumes minimum flowby = 7Q10 based on short affected stream segment · Does not require purchase of additional land · Approximately 59 acres of wetland impacts · Potential impacts to previously identified populations of James Spiny Mussel · Direct impact to 2 previously identified historic structures (eligibility not determined) · Potential indirect impacts to 4 previously identified historic properties (eligibility not determined); additional cultural resource surveys necessary · Potential displacement of 1 residence 32 willva\ 30502ho.p65 Construct Dam and Reservoir on North Fork Rivanna River Construction of a dam and reservoir on North Fork Rivanna River 2 miles west of the North Fork Filtration Plant. Includes: new 23 mgd intake and pump sta- tion, 11 mgd expansion of the S. Fork Rivanna Reservoir intake, pump stations and treatment plant, and a new 36-inch pipeline from the North Fork Rivanna pump station to the South Fork Rivanna River Reservoir. Normal pool elevation of new reservoir 490feet with surface area of 1,057 acres and storage capacity of 10, 059 million gallons. Drainage area of reservoir 63 square miles. Increase in safe yield - 15.4 million gallons per day Estimated cost - $79 million Will require land acquisition Assumes minimum flowby = 30% of mean annual flow Approximately 72 acres of wetland impacts Impacts to threatened/endangered species not known; additional surveys may be required Direct impacts to 4 previously identified archaeological sites (eligibility not determined); additional archaeological surveys required Potential indirect impacts to 3 previously identified historic properties (eligibility not determined); additional architectual surveys necessary Potential displacement of 2 residences 33 w.~va', 30502ho. D65 Construction of Dam and Reservoir on Preddy Creek Construction of a dam and reservoir on Preddy Creek 2.5 miles northeast of the North Fork Rivanna water treatment plant. Includes a new 9. 6 mgd intake struc- ture, raw water pump station, water treatment plant, finished water pump sta- tion, and a new 24-inch pipeline. Normal pool elevation of reservoir 460feet with surface area of 932 acres and storage capacity of 9,134 million gallons. Drainage area of reservoir 14 square miles. Increase in 2050 safe yield o 6.4 million gallons per day Estimated cost - $ 91 million Will require land acquisition Assumes minimum flowby = 30% of mean annual flow Approximately 77 acres of wetland impacts Impacts to threatened/endangered species undetermined; survey may be required Direct impacts to 4 previously identified historic structures (eligibility not determined); additional architectural surveys required Potential indirect imPacts to 3 previously identified historic properties (eligibility not determined); additional surveys necessary Potential displacement of 6 residences 34 w~tlva\ 30502ho.065 Construction of Dam and Reservoir on Mechums River Near Lake Albemarle Construction of a dam and reservoir on Mechums River 0.5 miles northeast of Batesville. Includes a new 20 mgd intake structure, 8 mgd expansion of the South Fork Rivanna Reservoir intake, raw water pump station, water treatment plant and finished water pump station. Normal pool elevation of reservoir 520 feet with surface area of 973 acres and storage capacity of 7,896 million gallons. Drainage area of reservoir 94 square miles. Increase in 2050 safe yield - 13.3 million gallons per day Estimated cost - $68 million Will require land acquisition Assumes minimum flowby = 30% of mean annual flow Approximately 107 acres of wetland impacts James Spiny Mussel previously identified in vicinity; will need to examine potential impacts Direct impacts to 1 archaeological site and 8 historic structures previously identified (eligibil- ity not determined); additional cultural resource surveys required Potential indirect impacts to 10 previously identified historic properties (eligibility not determined) · Potential displacement of 21 residences 35 willva', 30502ho.~65 Construction of Dam and Reservoir on Mechums River Near Midway Construction of dam and reservoir on Mecbums River one mile upstream of the 1-64. crossing near Midway. Includes a new 8.4 mgd intake structure. Normal pool elevation of reservoir 580feet with surface area of 477 acres and storage capacity of 3,477 million gallons. Drainage area of reservoir 34 square miles. · Increase in 2050 safe yield - 5.6 million gallons per day · Estimated cost - $26 million · Will require land acquisition · Assumes minimum flowby = 30% of mean annual flow · Approximately 52 acres of wetland impacts · James Spiny Mussel previously identified in vicinity; will need to examine potential impacts · Possible direct impac~ to 1 National Register Property (Miller School); will require furture investigation · Direct impact to 1 previously identified historic structure (eligibility not determined); additional architectural survey required · Potential indirect impacts to 5 previously identified historic properties (eligibility not determined); additional survey required · Potential displacement of 6 residences 36 willva\ 30502ho. D65 Construction of Dam and Reservoir on Buck Island Creek Construction of a dam and reservoir on Buck Island Creek 0.5 miles upstream of Route 53. Includes a new 22.5 mgd intake structure, raw water pump station, water treatment plant and finished water pump station. Normal pool elevation of reservoir 340feet with surface area 1, 707 acres and storage capacity of 13,950 million gallons. Drainage area of reservoir 38 square miles. · Increase in 2050 safe yield - 15 million gallons per day · Estimated cost - $118 million · Will require land acquisition · Assumes minimum flowby = 30% of mean annual flow · Approximately 103 acres of wetland impacts · Impacts to threatened/endangered species not determined; additional surveys may be re- quired · Direct impacts to 4 previously identified historic structures (eligibility not determined); additional cultural resource surveys required · Potential indirect impacts to 2 previously identified historic properties (eligibility not deter- mined) · Potential displacement of 14 residences 37 willva\ 30502ho. D65 Construction of Dam and Reservoir on Moormans River Construction ora dam and reservoir on Moormans Ri~er just downstream of confluence with Doyles Ri~er. Includes a new 17.4 mgd intake structure and 5.4 mgd expansion of the South Fork Rivanna River intake, raw water pump station, water treatment plant and finished water pump station. Normal pool elevation of reservoir 680feet with surface area of 817 acres and storage capacity of 9,202 million gallons. Drainage area of reservoir 53 square miles. · Increase in 2050 safe yield - 11.6 million gallons per day · Estimated cost - $106 million · Will require land acquisition · Assumes minimum flowby -- 30% of mean annual flow · Approximately 68 acres of wetland impacts · Impacts to threatened/endangered species not determined; additional surveys may be required · Direct impacts to 9 historic structures and 1 archaeological site previously identified (eligibility not determined); additional cultural resource surveys required · Potential indirect impacts to 5 previously identified historic properties (eligibility not deter- mined) · Potential displacement of 22 residences 38 willva\ 30502ho.p65 TRANSFER STATION CAPACI'rY SURVEY 3000 2500 2OOO m i500 Z 1000 500 0