Basin 7 Little Tennessee
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BASIN 7 LITTLE TENNESSEE BASIN DESCRIPTION The Little Tennessee Basin is one of six basins in North Carolina that drain the western slope of the Eastern Continental Divide and flow into the Tennessee River System. The basin is divided into the Little Tennessee River and the Tuckasegee River sub-basins. The Little Tennessee River begins in the mountains of the Chattahoochee National Forest in Rabun County, Georgia and flows north into Macon County, NC. The river is impounded by Fontana Dam about seven miles upstream of the Tennessee state line. The Tuckasegee River drains 737 square miles beginning in 1992 LWSP System Water Use from Basin (mgd) Jackson County. The river flows northwest then west and LWSP Residential Non-resid. Total Sub-basin merges with the Little Tennessee at Fontana Lake. Fontana Population Use Use Use* Lake is a multipurpose TVA facility with hydropower Little Tennessee R. 10,147 0.65 0.70 1.6 production and flood control as important benefits. Fontana Tuckasegee R. 6,975 0.42 0.45 1.0 Dam controls 1571 square miles of the Little Tennessee Basin. Total 17,122 1.1 1.1 2.6 Over 85% of the basin is forested. *Total Use includes unaccounted-for water and sales to other systems. WATER USE On average, residential and non-residential water use Factors Affecting Water Demand were nearly equal, with residential use accounting for 42% This basin is relatively undeveloped. However, there and non-residential use accounting for 45% basinwide. The has been significant population growth in communities in the remaining 13% was unaccounted-for water. region. Development of the casino on the Cherokee Indian LWSP systems expect to supply water to 32,810 Reservation is expected to expand the already successful persons by the year 2020, a 92% increase over 1992 levels. tourism industry in the region. This basin is home to about 1% Their demand for water is projected to grow 110% to 5.4 mgd of the State’s residents and contains all or part of 8 by 2020. municipalities in 6 counties. From 1990 to 1997 year-round In the 1992 LWSPs, 4 of the 7 systems using water population in three counties in this basin grew by 10% or from this basin reported that available supply was not more. adequate to meet estimated demand through 2002. DWR encourages systems to begin planning to Total Water Use in Basin manage and meet future water demands before average daily The U.S. Geological Survey’s (USGS) 1995 summary water use reaches 80% of a system’s available supply. In the of water use estimated total water use in the basin at 84.5 1992 LWSPs, five systems have plans to add an additional million gallons per day (mgd), almost exclusively from surface water supply totaling 3.6 mgd before demand exceeds 80% of water sources. USGS estimated total basin population at the system’s supply. 73,520. Residential demand was estimated at 3.7 mgd with about 37% (1.4 mgd) of this demand being supplied by public Self-supplied Use water systems. Overall, public water systems supplied 2 mgd The USGS estimated that self-supplied users, of surface water and 0.7 mgd of ground water for both excluding power generating facilities, accounted for 5 mgd of residential and non-residential uses. The remaining residential the mgd total of water used from this basin, as shown in the water demand was met by 2.3 mgd of self-supplied ground table below. Domestic use comprised 47% of the self-supplied water. In addition, there was about 2.7 mgd of self-supplied uses, followed by irrigation (37%), commercial (7%), livestock water withdrawn for non-residential water uses. (6%), and industrial (4%). Local Water Supply Plans (LWSPs) USGS Estimated Self-supplied Water Use in mgd Sub-basin Domestic Livestock Industrial Commercial Irrigation Total All units of local government that supply or plan to Little Tennessee 1.23 0.23 0.19 0.13 1.42 3.2 supply water to the public are required to develop a LWSP. Tuckasegee R. 1.11 0.06 0.00 0.21 0.45 1.8 The Division of Water Resources (DWR) reviews LWSPs and maintains a database of the LWSP information. Basin Total 2.3 0.3 0.2 0.3 1.9 !5.0 LWSPs were submitted by 7 public water systems having service area in this basin or using water from this basin. These systems supplied 2.6 mgd of water from this basin to 17,122 persons. The following table summarizes the LWSP population served with water from this basin and their water use for 1992. Registered Water Withdrawals SUMMARY OF INFORMATION FROM 1992 LWSPs Before 1999, anyone withdrawing 1.0 mgd or more of surface or ground water was required to registered that ! Per capita water use was 150 gallons per day in 1992 and is withdrawal with DWR. In this basin there are 14 registered projected to increase to 175 gallons per day by 2010. withdrawals other than LWSP systems or power generating facilities, with the cumulative capacity to withdraw 28 mgd. ! Six systems are not connected to another water supply Ten of these registered withdrawals are for surface water. In system. 1999, the registration threshold for all water uses except agriculture was lowered to 100,000 gallons per day. March 1, ! The reported raw water supply was 10.7 mgd surface water 2000 is the deadline for registering 1999 withdrawals.. and a 12-hour groundwater supply of 0.2 mgd. WATER AVAILABILITY !Demand-to- supply Ratios for 1992 and 2010: Surface water is the primary source of water for most of the residents of the basin. LWSPs indicate that 5 water 1992 2010 systems in these sub-basins withdraw about 1.9 mgd of surface # of Systems reporting 7 7 water. Local water supply plans show that 2 systems rely on reservoirs for all or part of their water supply. The combined # of Systems reporting ratio > 1.0 0 0 demand on these reservoirs averaged about 0.33 mgd in 1992. # of Systems reporting ratio > 0.9 0 0 The estimated available supply from these reservoirs, based on # of Systems reporting ratio > 0.8 0 0 the 20-year safe yield reported in local water supply plans, is # of Systems reporting ratio > 0.5 0 0 3.2 mgd. Four of the surface water systems submitting local water supply plans have run-of-river intakes. These intakes supplied about 1.6 mgd of water in 1992. The available supply from these sources, based on information reported in local water supply plans, is about 6.2 mgd. The ability to increase withdrawals in the basin depends on site-specific considerations of instream flow needs, water quality protection, and other environmental factors as well as financing and the ability to adjust contracts with owners of privately owned reservoirs. There are 2 systems in this basin using ground water. They have an overall capacity to pump 0.19 mgd of ground water based on the 12-hour yields supplied in their LWSPs. INTERBASIN TRANSFERS OF SURFACE WATER Across the state many water systems move surface water between sub-basins to meet their needs. The Town of Highlands straddles the Little Tennessee and Savannah River basins, resulting in an incidental transfer. Otherwise, there are no interbasin transfers associated with this basin. January 2000 Draft State Water Supply Plan DENR, Division of Water Resources 5-3 Pigeon River HAYWOOD TENNESSEE COUNTY Maggie Valley SD 7-2 JunaluskaClyde SD Tuskasegee River SWAIN Canton COUNTY Waynesville Bryson City Whittier Santeetlah GRAHAM COUNTY Tuckaseigee W&S Authority Robbinsville 5-2 JACKSON French Broad River 7-1 COUNTY Little Tennessee River Brevard Franklin TRANSYLVANIA COUNTY Andrews Marble Community Water System MACON Rosman CHEROKEE COUNTY COUNTY 6-1 Hiwassee River Highlands 8-1 Murphy CLAY Savannah River COUNTY Hayesville GEORGIA LEGEND Miles Basin 7 Little Tennesse 0 2 4 6 8 (unshaded basins) County Boundary Basin Boundary LITTLE TENNESSEE BASIN 1992 and 2010 Population and Water Usage as reported by LWSP systems located in or using water from this basin Water systems showing "Demand as % of Supply" above 80% should be actively planning to control and meet future demand. Water Sources: g - ground water, s - surface water, p - purchased water mgd - million gallons per day 7 LITTLE TENNESSEE Water Total Service Total Water Use in Reported Supply in Demand as % of BASIN Population mgd mgd Supply County Water System Source 1992 2010 1992 2010 1992 2010 1992 2010 GRAHAM ROBBINSVILLE s 2,370 2,868 0.30 0.36 0.9 1.2 33% 30% SANTEETLAH g 300 304 0.02 0.02 0.048 0.068 33% 29% JACKSON TUCKASEIGEE WSA sp 4,400 9,717 0.63 1.15 1.565 3.065 40% 38% MACON FRANKLIN s 6,500 8,500 0.81 1.82 5.1 5.1 16% 36% HIGHLANDS s 977 1,233 0.46 0.75 2.6 3.6 18% 21% SWAIN BRYSON CITY s 2,400 2,576 0.33 0.35 0.56 1.36 59% 26% WHITTIER SD g 175 198 0.01 0.01 0.144 0.144 7% 8% Total 17,122 25,396 2.56 4.46 11 15.