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HomeMy WebLinkAboutRWSA Sugar Hollow Res-Hydro Ast RIVANNA WATER AND SEWER AUTHORITY SUGAR HOLLOW RESERVOIR HYDROLOGIC ASSESSMENT DAA PROJECT NO. R00538.01 Prepared for: RIVANNA WATER AND SEWER AUTHORITY Charlottesville, Virginia Prepared by: DRAPER ADEN ASSOCIATES Richmond, Virginia July, 2000 RIVANNA WATER AND SEWER AUTHORITY SUGAR HOLLOW RESERVOIR HYDROLOGIC ASSESSMENT DAA PROJECT NO. R00538.01 This document, including all attachments, was prepared by Draper Aden Associates in accordance with a contract between Draper Aden Associates and the Rivanna Water and Sewer Authority. This document has been prepared by Draper Aden Associates in accordance with generally accepted standards of envkonmental practice for the exclusive use of the Rivanna Water and Sewer Authority, for specific application to the referenced site. No other warranty is either expressed or implied. Any reuse of this document by other parties, or for purposes other than those specified, without written authorization from Draper Aden Associates, will be at the sole risk of the party or parties utilizing this document. Draper Aden Associates shall incur no liability resulting from any and all claims, damages, losses, and expenses that might arise from unauthorized use of this document. Mark D.. Williams Environmental Scientist P. Matt Overton (MS) Project Biologist TABLE OF CONTENTS 1.0 SUMMARY 2.0 FIELD PROCEDURES/OBSERVATIONS 3.0 STREAM HYDROLOGY 4.0 ECOLOGICAL IMPACTS/BENEFITS 5.0 CONCLUSIONS 6.0 LIMITATIONS LIST OF APPENDICES APPENDIX 1 FIGURES RIVANNA WATER AND SEWER AUTHORITY SUGAR HOLLOW RESERVOIR HYDROLOGIC ASSESSMENT DAA PROJECT NO. R00538.01 1.0 SUMMARY The Sugar Hollow Reservoir is a 48 surface-acre drinking water supply reservoir located in Albemarle County at the base of the Blue Ridge Mountains (see vicinity map, APPENDIX 1). The reservoir system (Sugar Hollow and Ragged Mountain) currently supplies potable water to Charlottesville and surrounding urban areas by piping approximately 4 million gallons a day to the Observatory Treatment Plant. The reservoir was first established when a dam was built on the Moormans River in 1923. In 1946, a larger dam (the existing dam) was built to increase the capacity of the Sugar Hollow Reservoir. In 1999, an air bladder was constructed on the top of the dam to replace the gated spillway and steel structure in order to regulate the height of the dam within the upper five feet and to increase the spillway capacity. Since the existing dam was built in 1946, there is no requirement to release water from the reservoir to maintain a minimum in-stream flow. Consequently, downstream of the dam, the Moormans River experiences periods of no-flow during certain parts of the year. The primary purpose of this assessment is to enhance that body of hydrogeologic information that was prepared by others, and to assist the Rivanna Water and Sewer Authority in its assessment of the possible release of water from the reservoir. The secondary purpose of this hydrologic assessment is to determine whether the Moormans River ecological balance has been significantly disrupted due to the presence of the Sugar Hollow Dam. Rivanna Water and Sewer Authority Sugar Hollow Reservoir - Hydrologic p~ssessment DAA Project No. [R00538.01 July, 2000 i Page 2 Based upon available data from as long as 37 years ago, the stream hydrology does not appear to have changed significantly. During the "dry" months of the year (July, August, and Sep!ember), the stream gage present on the North Fork of the Moormans River and at the dam site ishowed periods of no flow. According to Rivanna personnel, during certain periods of no-flow in the North Fork, the South Fork had some flow in it. This would provide the lower stretches of the Moormans River with some source of hydrology; however, the gage at the dam site (before the large dam was constructed) showed that during at least two years, there was a record of no-flow in the Moormans below the confluence of the North and South Forks. Based on a cursory review of the ecological state of the watershed, there does not appeal to be a significant difference between upstream and downstream conditions. Riverine organisms were observed in the North and South Forks as well as downstream from the reservoir. It appears that although the Moormans River does go dry during certain periods, there is enough water available beneath the substrate (within the cobblestones) of the stream to support these riverine organisms (especially the benthic invertebrates, amphibians, and reptiles). The fish species define the only observed difference between upstream and downstream ecological communities. The Upstream reaches of the North and South Forks are dominated by stream fishes (i.e., minnows, cyprinids; and darters; percidae) found in fast moving waters (typical for these mountain streams). Conversely, the fishes observed downstream from the reservoir (i.e., sunfishes and bass; centrarchids) were those found mostly in slow moving pools that exist in the deeper portions of the stream even when there is no flow in the stream bed. Based on our investigations and calculations, we offer the following professional opinionS. · The presence of the Sugar Hollow Reservoir does not appear to be affecting the etiological community of the watershed significantly. · There have been records of no-flow in the North Fork of the Moormans and the M6ormans River below the confluence of the North and South Forks at the dam site; therefore,i periods of no-flow below the existing dam should be expected, especially during the dryi months (July, August, and September). · Any release from the reservoir would benefit the ecological communities downstreOm from the reservoir by replenishing oxygen to the deeper pools and making more habitats available to riverine fishes adapted to flowing currents. The natural condition would be to release an amount from the reservoir equal to the amount entering from the North and South. Forks. Based on historical stream gage data on the North Fork during the "dry" montl~s (July, August, September) and extrapolation to the South Fork, this would be approximately 0.4 million gallons per day (0.6 cfs). Rivanna Water and Sewe~ Authority Sugar Hollow Reservoir - Hydrologic Assessment DAA Project No. [00538.01 Iuly, 2000 Page 3 With regard to the ecological benefits, the optimal release to keep the streambed flowi~tg with an average depth of 6 inches would be 8.4 million gallons per day (average of 13 cfs. With regard to the volume of the reservoir, the optimal release to keep the streambed ~lowing during periods of no-flow into the reservoir (over 90 days) would be 0.8 million gallons per day (average of 1.23 cfs). This figure is only applicable in situations when drinking (vater is not withdrawn from Sugar Hollow. 2.0 FIELD PROCEDURES/OBSERVATIONS 2.1 Introduction Rivanna Water and Sewe~ Authority Sugar Hollow Reservoir - Hydrologic/~ssessment DAA Project No. ~t00538.01 ~luly, 2000 Page 4 On June 29 and July 6, 2000, Draper Aden personnel performed a preliminary survey of conditions along the Moormans River in western Albemarle County. The survey represe element of a stream-monitoring program developed by Draper Aden Associates to hel stream nts one assess potential impacts of the Sugar Hollow dam and reservoir on the environment. ' The results of this preliminary study suggest that the water quality and ecological commun: ties are not significantly affected by the presence of the dam. Conversely, we find some evid.~nce of environmental impact that indicates that the downstream channel experiences longer dry periods than the upstream areas. The results of this preliminary study do not support the hypotheses that (1) ecological impaq:ts from the dam preclude the presence of aquatic life in the subject stream, or that (2) the abs race of discharge from the dam to the stream is responsible for significant alteration of water qualit~ and/or ecological communities. Additional studies would be required in order to verify the apparellt effect of the dam on surface water. 2.2 Procedures Draper Aden Associates personnel observed ecological conditions in areas surrounding th Hollow Reservoir, and attempted to ascertain the current health of the ecosystem. The con( the associated streams was assessed, as well as the current reservoir levels. Streams were assessed according to their apparent water volumes and flows, and evidence of flora and fauna (and their associated health). Benthic invertebrates and fish organisms were captured using nets, and were otherwise observed in their natural setting. Stream width and depth were measured at several points along the stream from the dam to the first road crossing. The typical cross-section of the stream was determined to be an average )f these measurements. Hydrologic calculations were performed by Draper Aden personnel. 2.3 Observations On June 26, 2000, Draper Aden personnel observed three relevant stream locations, hydrol connected to the Sugar Hollow reservoir, and reported the following results. The water lev dam was high enough to cause a slight flow over the dam that covered approximately one one-half of the dam's area. Normal pool elevation levels were considered to be on the stre~ where heavy vegetation began to take root. e Sugar [ition of agically at the :hird to bank Rivanna Water and Sew~ ir Authority Sugar Hollow Reservoir - Hydrologic Assessment DAA Project No. !R00538.01 July, 2000 ! Page 5 North Fork, Moormans RiVer (approximately 300 feet upstream from I reservoir) - the stream volume appeared to be near its normal levels, and was flowing smoothly. Evidence of invertebrate species was found (such as the larvae of insects bt!longing to the Orders Ephemeroptera, mayflies; Plecoptera, stoneflies; and Tricl loptera, caddisflies - commonly referenced as the "EPT group" - indicators of got~d water quality), and minnow species were observed. Plants, especially sycamore 0 ~latanus occidentalis), were found growing throughout the streambed, providing evi, tence of the intermittent nature of the North Fork. Rocks in the center of the chan]lel were covered with dense algae. The channel is defined by cobbled rocks (most range in size from 3" to 12"), although some larger boulders are present. South Fork, Moormans River (approximately 200 feet upstream from res{~rvoir) - the stream volume appeared to be near its normal levels, and was flowing si noothly. Evidence of invertebrate species was found (also EPT group). No minno~ species were observed. Rocks throughout the channel were covered with long, flowing algal forms. The channel is defined by a base of bedrock, although boul. ters and smaller rocks are present. Moormans River (approximately 900 feet below the dam, site A) - thc stream volume appeared to be somewhat less than its normal levels, althougl it was flowing smoothly. Evidence of invertebrate species was found (those belt tging to the EPT group), although populations were not as prolific as had beep found upstream. Several large pools exist just downstream from the dam, and populations of larger fish (Oncorhynchus, trout; Micropterus, smallmouth bass and bluegill) and some minnow species were observed. Amphibian and reptile species were observed. Rocks in the center of the channel were covered with algae. The channel is defined by cobbled rocks (most range in size from 3" to 12"), althou, h some larger boulders are present. On July 6, 2000, Draper Aden personnel revisited two of the relevant stream locations, igcluding four specific sites on the Moormans River below the dam. Water was not spilling over Ithe dam when the observations were made. · North Fork, Moormans River - the stream volume appeared to be below it~ normal levels, although it was flowing smoothly. Evidence of significant invertebrate~ species was found (EPT group and Decapoda, crayfish), and minnow sped~ies were observed. Rocks in the center of the channel were covered with dense algae. The channel was measured as 15 feet wide, and water levels were approxin~ately 12 inches below normal at mid-stream. Rivanna Water and Sew~ r Authority Sugar Hollow Reservoir - Hydrologic ~ssessment DAA Project No. R00538.01 July, 2000 Page 6 / Moorrnans River (site A) - since there was not a surface water flow over t~e dam, the river's volume was low. Some flow was visible due to seepage along the side of the dam, as well as some groundwater input from the hills beside the stream. Evidence of some invertebrate species was found 0gPT group). Populalions of larger fish (trout, smallmouth bass, bluegill) and minnow species were olCserved, especially in the deeper pools. Amphibian and reptile species were observed, including tadpoles. Rocks in the center of the channel were covered with algae. The channel was measured as 21 feet wide and water levels were approximately 14 inches below normal at mid-stream. Just below site A, the fiver appeared ~try over intermittent spaces, although moisture was evident just below the substrate. ' Tributary to Moormans River (site B) - a tributary that drains the northerr Middle Mountain joins the main channel of the Moormans approximately 1 below the dam. Water was actively flowing in the unnamed tributary on tr. Evidence of some invertebrate species was found (EPT group). Plants exisl of the streambed. Rocks in the center of the channel were covered with al~ tributary channel was measured as 13 feet wide and water levels were appro: 12 inches below normal at mid-stream. After the addition of water fi tributary, the main channel did not appear dry again. A deep pool near provided habitat for several fish species (trout, smallmouth bass, bluegill, side of 100 feet is date. in most ae. The rimately om this this site darters, minnows), amphibians, and reptiles. ' Moormans River (site C) - approximately one-half mile below the dam, t~e main channel of the Moormans appears to change from loose cobble to bedrock. The water is relatively shallow, but the streambed is 22 feet wide with a relatively slow flow. Little evidence of invertebrate species was found due to the lack of suitable substrate. There was also little evidence of vertebrate species, with the exc4ption of amphibians and minnows; however, there were indications that mammals frequently visited this section of the river. The streambed was devoid of plantlife, again because of the bedrock substrate. Rocks in the center of the channel were !covered with algae. Water levels were approximately 16 inches below normal !at mid- stream. Just below this site, the stream appeared to diverge into three Iseparate channels All channels had a loose cobble substrate The southern ~hannel, approximately 8 feet wide, was dry. The northernmost channel (6 feet wide had an active flow. Between those two channels was a wide area that appeared x5 st, with large puddles, but was covered in dense vegetation. ! Rivanna Water and Sewe~ Authority Sugar Hollow Reservoir - Hydrologic k~ssessment DAA Project No. R00538.01 Moormans River (site D) - approximately three-fourths mile below the dm Route 614 crosses the river. Under the bridge, the channel of the Mt measures 30 feet wide. The water level appeared to be 12 inches below no~ substrate again consists of loose cobbles and boulders, and plants can be fi small islands throughout the streambed. Several invertebrate species were fi well as amphibians, reptiles, and minnows. Rocks in the center of the chain covered with long, flowing algal forms, indicating a more perennial natur stream. A small, unnamed tributary joins the river just above the bridge ¢ which drains the eastern side of Middle Mountain. Although this tribut appears intermittent in nature, it adds a significant amount of water Moormans under most circumstances. July, 2000 Page 7 n, State ~orlIlanS ~al. The ~und on ~und, as tel were to the tossing, ~ry also to the 3.0 / Rivanna Water and Sewe~ Authority Sugar Hollow Reservoir - Hydrologic ~ssessment DAA Project No. R00538.01 July, 2000 Page 8 STREAM HYDROLOGY 3.1 History of Flow Data The United States Geological Survey has monitored gages on the Moormans Rive~ on an intermittent basis since 1944. Three sites are relevant to the subject reservoir. Gage 02032000 was positioned on the Moormans where the dam is now located. It m mitored stream flows from late 1944 through 1946 (before the large dam was constructed). Dt~ring the summers of 1945 and 1946, the gage showed extended periods of no-flow in the chant el. It is important to note that the gage was downstream of the confluence of the North an:l South Forks; thus, there was little or no flow in either of those streams. Gage 02031500 is on the North Fork, approximately one-quarter mile upstream f:om the reservoir. It operated from 1952 to 1963, and again from 1982 to 1984. In each o~ the 15 summers studied, flows reached levels less than 2 cubic feet per second. In nine of the summers, a minimal flow of 0.2 cfs or less was measured, and during four of the s~tmmers, there were periods of no flow at all. Gage 02032250 is located on the Moormans River near the town of Free Union, upstre~,Lm of its confluence with the Mechums River. In 16 of the 18 summers between 1979 and 1997, the Moormans suffered from extremely low flows at the station (exceptions were 1989 and 1992). Flows were considered to be low at volumes of 10 cfs or less. 3.2 CalCUlated Release From Reservoir / As discussed above, the typical cross section of the Moormans River downstream of the reservoir is approximately 25 feet wide and 14 inches deep; this typical cross-section applies over the sl,retch of river from the dam to the first bridge crossing downstream. Based on the information liste9 above, Draper Aden Associates calculated the minimum release rate required to maintain a floW in the channel with a depth of 6 inches. An assumption was made that the water flows at an avelage rate of 1 foot/second, resulting in a release rate of 8.40 MGD (13 cfs). We also assunCed that evaporation in the channel below the reservoir is minimized due to the stream's canopy covlr. 3.3 Impacts to Volume of Reservoir . / / Based on discussions with Rivanna personnel, it is our understanding that the reservoiysystem currently supplies approximately 4 million gallons of water per day for a potable water supply with an approximate storage capacity of 360 million gallons in Sugar Hollow Reservoir. II. is also assumed that 80% of the volume of the reservoir should be maintained, resulting in a r~inimum storage of at least 288 million gallons (maximum release of 72 million gallons). / / Rivanna Water and Sewe: Sugar Hollow Reservoir - Hydrologic ~ DAA Project No. i The historical data indicates that there were periods when the North Fork achieved virtually: into the reservoir. Considering this, and the requirement for an effective volume to be mai~ approximately 72 million gallons of storage would be available for release to maintain flo~ downstream channel when there is no flow into the reservoir. As stated above, this amora only be released if drinking water was not withdrawn from this reservoir. Authority asessment [00538.01 July, 2000 Page 9 ~o flow ~tained, ~ in the tt could If a drought condition occurred for three consecutive months (90 days), an average daily release rate of 0.80 million gallons per day (1.23 cfs) could be achieved while maintaining the effective volume. This release rate would provide a 1 ¼" depth of water in the downstream channel. The release rate of 8.4 million gallons per day (13 cfs) could be safely maintained for approximately 8 days before the 80% volume of the reservoir would be compromised. Of course, tak/ng the drinking water withdrawal into account would decrease these numbers. Rivanna Water and Sewe Sugar Hollow Reservoir - Hydrologic ~ DAA Project No. 4.0 ECOLOGICAL IMPACTS/BENEFITS 4.1 Existing Conditions On June 26, 2000, Draper Aden personnel observed three relevant stream locations, hydrol Authority kssessment R00538.01 July, 2000 Page 10 ~)gically connected to the Sugar Hollow reservoir. The water level at the dam was high enough to [cause a slight flow over the dam that covered approximately one-third to one-half of the dam's area. I On July 6, 2000, Draper Aden personnel revisited two of the relevant stream locations, i~cluding four sites on the Moormans River below the dam (Figure 2). Water was not spilling overthe dam when the observations were made. Observations are described in SECTION 2.3. 4.2 Ecological Benefits of Additional Water We believe that any amount of water released from the reservoir (however minimal) will be ecological communities downstream by providing freshly oxygenated water, and providil habitats for organisms adapted to flowing streams. The natural condition would be to re amount from the reservoir equal to the amount entering from the North and South Forks. Some consideration must be made for periods of drought. Since these tributaries have history of no-flow periods, it should be expected that the Moormans River downstream wc experience periods of no-flow. It appears that the organisms found downstream of the have adapted to the intermittent nature of the stream. 4.2.1 Fish Species aefit the ~g more .ease an ;hown a uld also eservoir The release of any amount of water will benefit the fish species. A perennial stream will provide more suitable habitat for stream fishes adapted to flowing currents and riffles. It will p~ovide a supply of freshly oxygenated water to the deeper pools that exist during periods of no-flow, which harbor populations of fishes adapted to the slow moving water. 4.2.2 Reptiles and Amphibians / The release of water from the reservoir will not appear to significantly benefit the rel~tile and amphibian populations. No reptiles or amphibians were observed in the fast moving water of the North and South Forks. The reptiles and amphibians observed downstream from the dam ~ppeared to inhabit the slow moving, deeper pools that exist even during periods of no-flow. / Rivanna Water and Sewe[ Authority Sugar Hollow Reservoir - Hydrologic .~ssessment DAA Project No. R00538.01 i July, 2000 Page 11 4.2.3 Invertebrates Similar to the fish species, any amount of water released would provide more habitat if or the invertebrate species. Conversely, the invertebrate community appears to be thriving Under the intermittent nature of the stream. Although the stream below the dam appears to be dry, ithere is sufficient water beneath the substrate within the cobblestones and bedrock to support a i healthy invertebrate population. The EPT group members (indicators of good water quality) have ~dapted to slow moving areas, where larvae feed on sediment and detritus and burrow into the substrate during periods of drought. 4.3 Ecological Benefits for the James Spinymussel 4.3.1. Species Summary The James spinymussel (Pleuroberna collina) is confined to the upper James River l?asin in Virginia and West Virginia, and is extremely rare throughout its range because ofI habitat degradation and reproductive isolation in the tributaries. The species is known to inhabit Rocky Run, the Mechums River, and the Moormans River in Albemarle CoUnty, plus several other headwater areas in the James River basin. The James spinymussel is a lotic (flowing water) species that occurs in runs with moderate icurrent, and sand, gravel, and small cobble substrata. Extirpated populations resided in sandy boitoms of larger streams with swift currents; current populations occur in streams with hardness value~ greater than 50 mg calcium carbonate per liter. , Studies show that the spinymussel breeds in the summer. Several minnow species may act ias hosts to carry glochidia to new areas; glochidia then need a sandy substrate in which to bur~'ow and continue development. Threats to current populations include habitat competition with the Asian clam (Corbicula fluminea), sediment and erosion, and sewage and effluent from small communities. It was listed as federally endangered on July 22, 1988, and is extremely :are and endangered in Virginia. 4.3.2. Habitat Suitability The upper headwaters of the Moormans do not seem suitable for a James spinymussel popUlation. The lack of a sandy substrate would severely hinder the establishment of the species. Althgugh the species has been observed in lower portions of the river, near its confluence with the Mechums (which is close to Rocky Run), the cobbles and boulders of the Sugar Hollow section are not appropriate. Rivanna Water and Sewer Authority Sugar Hollow Reservoir ~ Hydrologic Assessment DAA Project No. R00538.01 July, 2000 Page 12 In addition, the intermittent nature of the stream flow in the headwaters, especially during the summer breeding season, would inhibit the establishment of a perennial population. Minnow species, acting as glochidial hosts, may also have their migration impeded by falling stream levels. Our professional conclusion is that even if water were released from the reservoir to provide a perennial habitat in the upper Moormans River, the substrate would preclude the James spinymussel from establishing a population in this area. 4.4 Extended Drought Conditions Draper Aden Associates personnel observed the Moormans River ecosystem during a period of moderate flow and a period without flow over the dam. Conclusions are based upon the health of the stream at the time of observation. A re-examination of the stream's health after a period of extended drought is highly recommended in order to confirm whether the conclusions are valid. It appears that the channel of the Moormans River will be dry for long stretches between the dam and its confluence with the Mechums River. The deep pools that harbor populations of fish, reptiles, and amphibians should remain intact. The absence of vegetation in the center of the river also shows that there is at least some flow during most of the summer; this may be the result of groundwater recharge from the surrounding hillsides and infiltration from some of the smaller tributaries. It is unknown whether the soil is saturated just beneath the cobbled substrate. As discussed above, the listed vertebrates can continue to thrive in the deeper pools that exist perennially. The insects have adapted to intermittent stream cycles. Larvae emerge in still water and stagnant pools, and can stop development and burrow into the substrate if water levels drop. Adults develop and reproduce as their habitat again becomes inundated. 5.0 CONCLUSIONS Rivanna Water and Sewer Authority Sugar Hollow Reservoir - Hydrologic Assessment DAA Project No. R00538.01 July, 2000 Page 13 Based on our investigations and calculations, we offer the following professional opinions. · The presence of the Sugar Hollow Reservoir does not appear to be affecting the ecological community of the watershed significantly. There have been records of no-flow in the North Fork of the Moormans and the Moormans River below the confluence of the North and South Forks at the dam site; therefore, periods of no-flow below the existing dam should be expected, especially during the dry months (July, August, and September). Any release from the reservoir would benefit the ecological communities downstream from the reservoir by replenishing oxygen to the deeper pools and making more habitats available to riverine fishes adapted to flowing currents. The natural condition would be to release an amount from the reservoir equal to the amount entering from the North and South Forks. Based on historical stream gage data on the North Fork during the "dry" months (July, August, September) and extrapolation to the South Fork, this would be approximately 0.4 million gallons per day (0.6 cfs). · With regard to the ecological benefits, the optimal release to keep the streambed flowing with an average depth of 6 inches would be 8.4 million gallons per day (average of 13 cfs). With regard to the volume of the reservoir, the optimal release to keep the streambed flowing during periods of no-flow into the reservoir (over 90 days) would be 0.8 million gallons per day (average of 1.23 cfs). This figure is only applicable in situations when drinking water is not withdrawn from Sugar Hollow. Rivanna Water and Sewer Authority Sugar Hollow Reservoir - Hydrologic Assessment DAA Project No. R00538.01 July, 2000 Page 14 6.0 LIMITATIONS This document was prepared by Draper Aden Associates in accordance with generally accepted standards of environmental practice for the exclusive use of the referenced client, for specific application to the referenced site. No other warranty is either expressed or implied. Any reuse of this document by other parties, or for purposes other than those specified, without written authorization from Draper Aden Associates, will be at the sole risk of the party or parties utilizing this document. Draper Aden Associates shall incur no liability resulting from any and all claims, damages, losses, and expenses that might arise from unauthorized use of this document. Conclusions presented in this report are based upon a review of available information, the results of our field studies, and professional judgment. Our conclusions do not reflect variations in field conditions that might exist between or beyond the specified sampling stations or at any time other than the date specified. APPENDIX 1 FIGURES SOURCE: USGS 7.5' QUADRANGLE BROWNS COVE. VIRGINIA PREPARED 1984 DRAPER ADEN ASSOCIATES - ENVIRONMENTAL SERVICES CLIENT: RIVANNA WATER AND SEWER AUTHORITY FACILITY: SUGAR HOLLOW RESERVOIR LOCATION: WHITEHALL. VIRGINIA PROJECT: MOORMANS RIVER ASSESSMENT :)E$1GN: =ROJECT: VICINITY MAP MDW IDRAW,: DGL. JAPPROVED: MDW IFILE: R00538 R00535.01IDATE= 07-18-00ISCALE: NTS IFIOURE: I SOURCE: USGS 7.5' QUADRANGLE BROWNS COVE, VIRGINIA PREPARED 1984 DRAPER ADEN ASSOCIATES - ENVIRONMENTAL SERVICES CLIENT: FACILITY: LOCATION: PROJECT: RIVANNA WATER AND SEWER AUTHORITY SUGAR HOLLOW RESERVOIR WHITEHALL, VIRGINIA MOORMAN$ RIVER ASSESSMENT MDW PROJECT: R00538,01 OBSERVATION SITES DGL APPROVED: MDW DATE: D7o18.00 NT*S R0~538 2