Basin 5 French Broad
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BASIN 5 FRENCH BROAD Basin Description The French Broad Basin is one of six basins in North Carolina that drain the western slope of the Eastern Continental Divide and flow into the Mississippi River System emptying into the Gulf of Mexico. The basin is divided into the French Broad River, the Nolichucky River, and the Pigeon River sub-basins, none of which merge in North Carolina. The French Broad River begins in the mountains of Transylvania County and flows north entering Tennessee north of Hot Springs, NC. The Pigeon River drains Hayward County LWSPs were submitted by 23 public water systems paralleling Interstate 40 north of Canton, NC, and flows into having service area in this basin or using water from this basin. Tennessee. The Nolichucky River is formed by the These systems supplied 38.2 mgd of water to 202,596 persons. convergence of the North Toe River and Cane River north of DWR estimated that 200,084 of the 202,596 persons served by Burnsville, NC. This sub-basin drains the western slope of the these 23 LWSP systems received water from this basin. Of the Blue Ridge north from Mount Mitchell to the Tennessee state 38.2 mgd supplied by these 23 LWSP systems, 38.1 mgd line. The Nolichucky and Pigeon rivers merge with the French comes from water sources in the French Broad Basin, the rest Broad in Douglas Lake, east of Knoxville, Tennessee. These coming from wells in adjoining basins. three sub-basins drain 2816 square miles in North Carolina and about 1500 square miles in Tennessee upstream of Douglas 1992 LWSP SystemWater Use from Basin (mgd) Lake. Extensive portions of this basin lie within the boundaries LWSP Residential Non-residential Total Sub-basin of the Pisgah and Cherokee national forests. Population Use Use Use* Nolichucky R. 6,359 0.47 0.60 1.5 WATER USE French Broad R. 166,165 10.59 11.37 30.6 Factors Affecting Water Demand Pigeon R. 27,560 1.50 0.91 6.0 This basin has about 5% of the State’s residents and Total 200,084 12.6 12.9 38.1 *Total Use includes unaccounted-for water, bulk sales to other systems . contains all or part of 25 municipalities in 10 counties. Asheville, one of the state’s 12 major metropolitan areas, gets On average, residential and non-residential water uses its water supply from this basin. From 1990 to 1997 year- were nearly equal, with residential use accounting for 33% and round population in three counties in this basin grew by 10% non-residential use accounting for 34% basinwide. or more. Over half of the land in the basin is forested. Unaccounted-for water was 27% of total use. LWSP systems expect to supply water to over Total Water Use in Basin 350,000 persons by the year 2020, a 75% increase over 1992 The U.S. Geological Survey’s (USGS) 1995 summary levels. Their demand for water is projected to grow 45% to of water use estimated total water use in the basin at 169 55.3 mgd by 2020. million gallons per day (mgd), with just over two-thirds In the 1992 LWSPs, 8 of the 23 systems using water coming from surface water sources. USGS estimated total from this basin reported that available supply was not adequate basin population at 385,590. Residential demand was to meet estimated demand through 2002. estimated at 24.5 mgd with about two-thirds of this demand DWR encourages systems to begin planning to being supplied by public water systems. Overall, public water manage and meet future water demands before average daily systems supplied 36.6 mgd form surface water and 2.6 mgd water use reaches 80% of a system’s available supply. Data for from ground water for both residential and non-residential 1992 indicated that 10 of the 23 LWSP systems in this basin uses. The remaining residential water demand was met by 8.5 had an average demand above this threshold. By 2020, 11 mgd of self-supplied ground water. In addition, there was systems project demand levels that will exceed 80% of their about 43.3 mgd of self-supplied water withdrawn for non- available supply. residential water uses. Self-supplied Use Local Water Supply Plans (LWSPs) The USGS estimated that self-supplied users, All units of local government that supply or plan to excluding power generating facilities, accounted for 52 mgd of supply water to the public are required to develop a LWSP. the 169 mgd total of water used from this basin, as shown in The Division of Water Resources (DWR) reviews LWSPs and the table below. Industrial use comprised 60% of the self- maintains a database of the LWSP information. The current supplied uses, followed by irrigation (19%), domestic (16%), database reflects water use information for 1992. livestock (4%), and commercial (1%). USGS Estimated Self-supplied Water Use in mgd Sub-basin Domestic Livestock Industrial Commercial Irrigation Total SUMMARY OF INFORMATION FROM 1992 LWSPs Nolichucky R. 1.65 0.21 0.00 0.18 2.21 4.3 !Per capita water use in gallons per day: French Broad R. 6.18 1.11 4.85 0.46 6.72 19.3 Sub-basin 1992 2010 Pigeon R. 0.62 0.52 26.17 0.08 0.76 28.2 Nolichucky River 240 258 Basin Total 8.5 1.8 31.0 0.7 9.7 51.7 French Broad River 182 150 Pigeon River 217 221 Registered Water Withdrawals Before 1999, anyone withdrawing 1.0 mgd or more of !Ten systems are not connected to another water supply surface or ground water was required to registered that system, including all of the systems in the Nolichucky sub- withdrawal with DWR. In this basin there are 42 registered basin and systems in Madison and Transylvania Counties. withdrawals other than LWSP systems or power generating facilities, with the cumulative capacity to withdraw 227 mgd. !Four systems rely on purchase water as their sole supply. Forty-one of these registered withdrawals are from surface water. In 1999, the registration threshold for all water uses !LWSPs in the French Broad sub-basin are not compatible except agriculture was lowered to 100,000 gallons per day. due to discrepancies with interconnection data. March 1, 2000 is the deadline for registering 1999 withdrawals. !These systems used about 36 mgd of surface water and approximately 2 mgd of ground water. WATER AVAILABILITY Surface water is the primary source of water for !The reported raw water supply was 54.7 mgd of surface most of the residents of the basin. LWSPs indicate that water and a 12-hour groundwater supply of 1.9 mgd. 11water systems in these sub-basins withdrew about 36.3 mgd of surface water in 1992. Local water supply plans show that !Asheville and Buncombe and Henderson Counties have 6 systems rely on reservoirs for all or part of their water formed a regional water system; Madison County is planning supply. The combined demand on these reservoirs averaged to develop a county system. about 27.5 mgd in 1992. The estimated available supply from these reservoirs, based on the 20-year safe yield reported in !Five systems were planning new supplies in the 1992 local water supply plans, is 27.2 mgd. LWSPs. Eight of the surface water systems submitting local water supply plans have run-of-river intakes. These intakes !The systems are projecting significant growth, 75% in supplied about 8.8 mgd of water in 1992. The available supply population and 45% in demand, through 2020. from these sources, based on information reported in local water supply plans, is about 27.5 mgd. Maggie Valley !About 10 mgd of additional water supply will be needed by Sanitary District has a 3 mgd withdrawal limit from Campbell water systems in the basin to ensure that water demands in and Jonathan creeks set by DWR based on instream flow 2010 do not exceed 80% of available supply, over 9 mgd of requirements. which will be needed in the French Broad sub-basin. In late 1999, Asheville completed an intake and water treatment plant on the Mills River. Weaverville has plans to !Demand to supply ratios for 1992 and 2010: install an new intake on the Ivy River. There are 9 systems in this basin using ground water. 1992 2010 They have an overall capacity to pump 1.9 mgd of ground # of systems reporting 23 23 water based on the 12-hour yields supplied in their LWSPs. # of systems reporting ratio > 1 5 7 # of systems reporting ratio > 0.9 7 8 INTERBASIN TRANSFERS OF SURFACE WATER Across the state many water users and systems move # of systems reporting ratio > 0.8 10 10 water between sub-basins to meet their needs. The table below # of systems reporting ratio > 0.5 12 14 indicates the number of potential interbasin transfers associated with this basin. Potential Interbasin Transfers based on 1992 data Sub-basin Number mgd OUT mgd IN Nolichucky River 0 0 0 January 2000 Draft French Broad River 3 0.103 0 State Water Supply Plan Pigeon River 0 0 0 DENR, Division of Water Resources Most of the transfer amount shown in the table is due to Hendersonville’s transfer to the Broad Basin. Beech Mountain Boone Elk Park BannerSeven Elk Devils Blowing Rock MITCHELL Newland COUNTY AVERY COUNTY Bakersville 5-1 CaldwellCALDWELL Co N Nolichucky River COUNTY Burnsville Spruce Pine TENNESSEE Hot Springs Lenoir Caldwell Co SE YANCEY 3-1 MADISON CaldwellJoyceton Co Water W Works COUNTY COUNTY Little Switzerland Catawba River Hudson Mars Hill Baton WC BURKE Sawmills Marshall COUNTY Granite Falls Caldwell Co S 5-2 Drexel MCDOWELL Morganton Valdese French Broad River Icard Township WC COUNTY 5-3 Weaverville Pigeon River Marion Burke Co.