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Home , Hiwassee River

BASIN 6 HIWASSEE RIVER

BASIN DESCRIPTION The Hiwassee River Basin is one of six basins in 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 drains 641 square miles of Clay and counties and is part of a 2099 square mile basin that begins in , flows through North Carolina, and merges with the River at in eastern Tennessee. The entire river is regulated by the Authority for hydropower production. Three dams in North Carolina form , Hiwassee Lake, and Apalachia Lake. The basin is predominantly mountainous with over 80% of the land area On average, residential and non-residential water use forested, much of it in the Nantahala National Forest. were nearly equal, with both residential and non-residential use accounting for about 37% basinwide. The remaining 24% WATER USE was unaccounted-for water. Factors Affecting Water Demand LWSP systems expect to supply water to 10,787 This basin is home to less than 1% of the State’s persons by the year 2020, a 40% increase over 1992 levels. residents and contains all or part of 3 municipalities in Clay Their demand for water is projected to grow 57% to 2.5 mgd and Cherokee counties. From 1990 to 1997 year-round by 2020. population in both counties grew by over 10%. In the 1992 LWSPs, 2 of the 4 systems using water from this basin reported that available supply was not adequate Total Water Use in Basin to meet estimated demand through 2002. The U.S. Geological Survey’s (USGS) 1995 summary DWR encourages systems to begin planning to of water use estimated total water use in the basin at 11.1 manage and meet future water demands before average daily million gallons per day (mgd), with 85% coming from surface water use reaches 80% of a system’s available supply. Data for water sources. USGS estimated total basin population at 1992 indicated that none of the LWSP systems in this basin 28,910. Residential demand was estimated at 1.7 mgd with had average demand above this threshold. By 2020, 2 systems about 40% of this demand being supplied by public water project demand levels that will exceed 80% of their available systems. Overall, public water systems supplied 1.4 mgd of supply. surface water and 0.25 mgd of ground water for both residential and non-residential uses. The remaining residential Self-supplied Use water demand was met by 1 mgd of self-supplied ground The USGS estimated that self-supplied users, water. In addition, there was about 0.9 mgd of self-supplied excluding power generating facilities, accounted for 9.5 mgd water withdrawn for non-residential water uses. of the 11.1 mgd total of water used from this basin, as shown in the table below. Livestock use dominated self-supplied uses Local Water Supply Plans (LWSPs) consuming 83% followed by domestic (11%), irrigation (5%), All units of local government that supply or plan to and commercial (<1%). supply water to the public are required to develop a LWSP. The Division of Water Resources (DWR) reviews LWSPs and USGS Estimated Self-supplied Water Use in mgd maintains a database of the LWSP information. The current Sub-basin Domestic Livestock Industrial Commercial Irrigation Total database reflects water use information for 1992. Hiwassee R 1.05 7.89 0.00 0.06 0.50 10 LWSPs were submitted by 4 public water systems having service areas in this basin or using water from this basin. These systems supplied 1.6 mgd of water to 7,725 Registered Water Withdrawals persons. All of the water supplied to customers came from this Before 1999, anyone withdrawing 1.0 mgd or more of basin. The following table summarizes the LWSP population surface or ground water was required to registered that served with water from this basin and their water use for 1992. withdrawal with DWR. In this basin there are no other registered withdrawals besides the LWSP systems. In 1999, the registration threshold for all water uses except agriculture 1992 LWSP System Water Use from Basin (mgd) was lowered to 100,000 gallons per day. March 1, 2000 is the Total LWSP Residential Non-resid. Total Sub-basin deadline for registering 1999 withdrawals. Population Population Use Use Use* Hiwassee River 28,910 7,725 0.60 0.59 1.6 *Total Use includes unaccounted-for water and sales to other systems. WATER AVAILABILITY SUMMARY OF INFORMATION FROM 1992 LWSPs LWSPs indicate that 2 water systems in this basin (Andrews and Murphy) withdrew about 1.4 mgd of surface !Per capita water use was 205 gallons in 1992 and is projected water in 1992. to increase to 213 gallons per day by 2010. The other two systems in this basin (Hayesville and Marble) depend on ground water, supplying an average of 0.2 !All water systems within the Hiwassee River Basin are mgd in 1992. They have an overall capacity to supply 0.35 isolated and can not feasibly connect to any other water mgd of ground water based on the 12-hour yields supplied in supplier. their LWSPs. Surface water will continue to be a significant source !The systems used 1.38 mgd from surface water and 0.21 mgd of water for public water systems in the basin. Local water ground water. supply plans show that Andrews’ reservoir and run-of-river intake can supply up to 0.88 mgd based on 20-year safe yield !The reported raw water supply was 81.13 mgd of surface estimates, of which about 0.7 mgd was used in 1992. water and a 12-hour groundwater supply of 0.35 mgd. Murphy, the other surface water system, has two run- of-river intakes with an estimated 20-year safe yield of 80.25 !The systems are projecting 40% growth in population and mgd, of which 0.7 mgd was used in 1992. 57% growth in demand through 2020.

INTERBASIN TRANSFERS OF SURFACE WATER !There are 3 systems that will exceed 80 percent of their Across the state many water users and systems move available supply by 2010 based on information provided in water between sub-basins to meet their needs. The service their local water supply plan. areas of the four local water supply plan systems in the basin do not overlap any basin boundaries and all water sources are !About 0.5 mgd of additional water supply will be needed by located within the basin. Therefore, there are no potential water systems to ensure that water demands in 2010 do not interbasin transfer issues at this time for any of these systems. exceed 80% of available supply.

!Demand-to-Supply Ratios for 1992 and 2010:

1992 2010 # of Systems reporting 19 19 # of Systems reporting ratio > 1 0 2 # of Systems reporting ratio > 0.8 0 2 # of Systems reporting ratio > 0.5 3 3

January 2000 Draft State Water Supply Plan DENR, Division of Water Resources Maggie Valley SD 7-2 Tuskasegee River

SWAIN COUNTY Waynesville

Bryson City Whittier

Santeetlah GRAHAM COUNTY Tuckaseigee W&S Authority

Robbinsville

JACKSON 7-1 COUNTY TENNESSEE Little

Franklin 6-1 Andrews Hiwassee River Marble Community Water System MACON CHEROKEE COUNTY COUNTY

Highlands Murphy CLAY COUNTY 8-1 Hayesville

13-1 Ocoee River GEORGIA

LEGEND Miles Basin 6 Hiwassee River 0 2 4 6 8 (unshaded basin) County Boundary Basin Boundary HIWASSEE 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 6 HIWASSEE BASIN Water Total Service Total Water Use in Reported Supply in Demand as % of Population mgd mgd Supply County Water System Source 1992 2010 1992 2010 1992 2010 1992 2010 * CHEROKEE ANDREWS s 3,010 4,299 0.69 0.99 0.88 0.88 78% 112% MARBLE g 1,105 1,500 0.08 0.13 0.1301 0.1301 60% 101% MURPHY s 2,800 2,850 0.69 0.78 80.25 80.25 1% 1% CLAY HAYESVILLE g 810 867 0.13 0.14 0.216 0.216 60% 63% Total 7,725 9,516 1.58 2.03 81 81