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 paralleling Interstate 40 north of Canton, NC, and flows into Tennessee. The Nolichucky River is formed by the convergence of the North Toe River and Cane River north of Burnsville, NC. This sub-basin drains the western slope of the Blue Ridge north from Mount Mitchell to the Tennessee state line. The Nolichucky and Pigeon rivers merge with the French Broad in Douglas Lake, east of Knoxville, Tennessee. These three sub-basins drain 2816 square miles in North Carolina and about 1500 square miles in Tennessee upstream of Douglas Lake. Extensive portions of this basin lie within the boundaries of the Pisgah and Cherokee national forests.

LWSPs were submitted by 23 public water systems having service area in this basin or using water from this basin. These systems supplied 38.2 mgd of water to 202,596 persons. DWR estimated that 200,084 of the 202,596 persons served by these 23 LWSP systems received water from this basin. Of the 38.2 mgd supplied by these 23 LWSP systems, 38.1 mgd comes from water sources in the French Broad Basin, the rest coming from wells in adjoining basins. 1992 LWSP SystemWater Use from Basin (mgd) Sub-basin Nolichucky R.

WATER USE Factors Affecting Water Demand This basin has about 5% of the State’s residents and contains all or part of 25 municipalities in 10 counties. Asheville, one of the state’s 12 major metropolitan areas, gets its water supply from this basin. From 1990 to 1997 yearround population in three counties in this basin grew by 10% or more. Over half of the land in the basin is forested. Total Water Use in Basin The U.S. Geological Survey’s (USGS) 1995 summary of water use estimated total water use in the basin at 169 million gallons per day (mgd), with just over two-thirds coming from surface water sources. USGS estimated total basin population at 385,590. Residential demand was estimated at 24.5 mgd with about two-thirds of this demand being supplied by public water systems. Overall, public water systems supplied 36.6 mgd form surface water and 2.6 mgd from ground water for both residential and non-residential uses. The remaining residential water demand was met by 8.5 mgd of self-supplied ground water. In addition, there was about 43.3 mgd of self-supplied water withdrawn for nonresidential water uses. Local Water Supply Plans (LWSPs) All units of local government that supply or plan to supply water to the public are required to develop a LWSP. The Division of Water Resources (DWR) reviews LWSPs and maintains a database of the LWSP information. The current database reflects water use information for 1992.

French Broad R.

LWSP Population

Residential Use

Non-residential Use

Total Use*

6,359

0.47

0.60

1.5

166,165

10.59

11.37

30.6

Pigeon R.

27,560

1.50

0.91

6.0

Total

200,084

12.6

12.9

38.1

*Total Use includes unaccounted-for water, bulk sales to other systems .

On average, residential and non-residential water uses were nearly equal, with residential use accounting for 33% and non-residential use accounting for 34% basinwide. Unaccounted-for water was 27% of total use. LWSP systems expect to supply water to over 350,000 persons by the year 2020, a 75% increase over 1992 levels. Their demand for water is projected to grow 45% to 55.3 mgd by 2020. In the 1992 LWSPs, 8 of the 23 systems using water from this basin reported that available supply was not adequate to meet estimated demand through 2002. DWR encourages systems to begin planning to manage and meet future water demands before average daily water use reaches 80% of a system’s available supply. Data for 1992 indicated that 10 of the 23 LWSP systems in this basin had an average demand above this threshold. By 2020, 11 systems project demand levels that will exceed 80% of their available supply. Self-supplied Use The USGS estimated that self-supplied users, excluding power generating facilities, accounted for 52 mgd of the 169 mgd total of water used from this basin, as shown in the table below. Industrial use comprised 60% of the selfsupplied uses, followed by irrigation (19%), domestic (16%), livestock (4%), and commercial (1%).

USGS Estimated Self-supplied Water Use in mgd Sub-basin

SUMMARY OF INFORMATION FROM 1992 LWSPs !Per capita water use in gallons per day:

Domestic

Livestock

Industrial

Commercial

Irrigation

Total

Nolichucky R.

1.65

0.21

0.00

0.18

2.21

4.3

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 surface or ground water was required to registered that withdrawal with DWR. In this basin there are 42 registered withdrawals other than LWSP systems or power generating facilities, with the cumulative capacity to withdraw 227 mgd. Forty-one of these registered withdrawals are from surface water. In 1999, the registration threshold for all water uses except agriculture was lowered to 100,000 gallons per day. March 1, 2000 is the deadline for registering 1999 withdrawals. WATER AVAILABILITY Surface water is the primary source of water for most of the residents of the basin. LWSPs indicate that 11water systems in these sub-basins withdrew about 36.3 mgd of surface water in 1992. Local water supply plans show that 6 systems rely on reservoirs for all or part of their water supply. The combined demand on these reservoirs averaged about 27.5 mgd in 1992. The estimated available supply from these reservoirs, based on the 20-year safe yield reported in local water supply plans, is 27.2 mgd. Eight of the surface water systems submitting local water supply plans have run-of-river intakes. These intakes supplied about 8.8 mgd of water in 1992. The available supply from these sources, based on information reported in local water supply plans, is about 27.5 mgd. Maggie Valley Sanitary District has a 3 mgd withdrawal limit from Campbell and Jonathan creeks set by DWR based on instream flow requirements. In late 1999, Asheville completed an intake and water treatment plant on the Mills River. Weaverville has plans to install an new intake on the Ivy River. There are 9 systems in this basin using ground water. They have an overall capacity to pump 1.9 mgd of ground water based on the 12-hour yields supplied in their LWSPs. INTERBASIN TRANSFERS OF SURFACE WATER Across the state many water users and systems move water between sub-basins to meet their needs. The table below indicates the number of potential interbasin transfers associated with this basin.

!Ten systems are not connected to another water supply system, including all of the systems in the Nolichucky subbasin and systems in Madison and Transylvania Counties. !Four systems rely on purchase water as their sole supply. !LWSPs in the French Broad sub-basin are not compatible due to discrepancies with interconnection data. !These systems used about 36 mgd of surface water and approximately 2 mgd of ground water. !The reported raw water supply was 54.7 mgd of surface water and a 12-hour groundwater supply of 1.9 mgd. !Asheville and Buncombe and Henderson Counties have formed a regional water system; Madison County is planning to develop a county system. !Five systems were planning new supplies in the 1992 LWSPs. !The systems are projecting significant growth, 75% in population and 45% in demand, through 2020. !About 10 mgd of additional water supply will be needed by water systems in the basin to ensure that water demands in 2010 do not exceed 80% of available supply, over 9 mgd of which will be needed in the French Broad sub-basin. !Demand to supply ratios for 1992 and 2010:

# of systems reporting # of systems reporting ratio > 1 # of systems reporting ratio > 0.9 # of systems reporting ratio > 0.8 # of systems reporting ratio > 0.5

1992 23 5 7 10 12

2010 23 7 8 10 14

Potential Interbasin Transfers based on 1992 data Sub-basin

Number

mgd OUT

mgd IN

Nolichucky River

0

0

0

French Broad River

3

0.103

0

Pigeon River

0

0

0

Most of the transfer amount shown in the table is due to Hendersonville’s transfer to the Broad Basin.

January 2000 Draft State Water Supply Plan DENR, Division of Water Resources

Boone

Beech Mountain Elk Devils Elk Park Banner Seven

Blowing Rock

MITCHELL COUNTY

Newland

AVERY COUNTY

Bakersville

E SE S NE N TE

5-1 Nolichucky River Burnsville

COUNTY

Spruce Pine

Hot Springs

YANCEY COUNTY

MADISON COUNTY

CALDWELL Caldwell Co N Lenoir Caldwell Co SE

3-1 Catawba River

Little Switzerland

Mars Hill

BURKE COUNTY

Marshall

5-2 French Broad River

5-3 Pigeon River

MCDOWELL COUNTY

Weaverville

Marion

BUNCOMBE Woodfin COUNTY

HAYWOOD COUNTY

7-2 Tuskasegee River

3-2 South Fork Catawba River

Old Fort

Asheville Canton Biltmore Forest

Clyde Waynesville

Bryson City

Whittier

Lake Lure

HENDERSON COUNTY

Tuckaseigee W&S Authority

Hendersonville

JACKSON COUNTY

7-1 Little Tennessee River

MACON COUNTY

Rosman

10

15

20

Bostic Forest City Ellenboro Alexander Mills

CLEVELAND COUNTY Shelby

Saluda

Boiling Springs

Columbus Tryon

Grover

SOUTH CAROLINA

8-1 Savannah River

Basin 5 French Broad

Miles

Fallston Lawndale Cleveland Co SD

Sandy Mush WA Brevard

Highlands

RUTHERFORD COUNTY

1-1 Broad River

POLK COUNTY

Laurel Park

TRANSYLVANIA COUNTY

Franklin

5

Burke Co.

Montreat Black Mountain

Maggie Valley SD Junaluska SD

SWAIN COUNTY

0

Caldwell W Works JoycetonCo Water Hudson Baton WC Sawmills Granite Falls Caldwell Co S Drexel Valdese Morganton Icard Township WC

(unshaded basins)

LEGEND County Boundary

Basin Boundary

FRENCH BROAD 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

5

FRENCH BROAD BASIN

County

Water System

Water

Total Service Population Source* 1992 2010

AVERY BUNCOMBE

NEWLAND g ASHEVILLE s BILTMORE FOREST p BLACK MOUNTAIN g MONTREAT g WEAVERVILLE sp WOODFIN sgp HAYWOOD CANTON s CLYDE p JUNALUSKA SD p MAGGIE VALLEY SD s WAYNESVILLE s HENDERSON HENDERSONVILLE s LAUREL PARK p MADISON MARS HILL s MARSHALL g MC DOWELL LITTLE SWITZERLAND COMM g WA MITCHELL BAKERSVILLE g SPRUCE PINE sg SALUDA p TRANSYLVANIA BREVARD s ROSMAN g YANCEY BURNSVILLE s Total

Total Water Use in mgd 1992 2010

mgd - million gallons per day

Reported Supply in mgd 1992 2010

Demand as % of Supply 1992 2010

645 99,000 1,321 5,750 637 3,300 7,000 7,000 1,350 3,550 5,510 10,150 40,000 1,100 2,950 809 270

900 167,200 1,501 6,878 750 4,806 7,903 7,200 1,703 4,290 7,870 11,570 59,992 1,711 4,210 794 330

0.11 21.50 0.21 0.57 0.14 0.43 1.00 1.44 0.16 0.28 0.92 3.21 5.57 0.11 0.25 0.12 0.01

0.15 28.00 0.23 0.63 0.16 0.63 1.10 1.75 0.20 0.33 1.31 3.62 7.21 0.17 0.47 0.12 0.01

0.257 24.59 0.205 0.401 0.3982 0.357 0.8335 6 1 0.375 0.875 12.502 6.6 1 0.278 0.748 0.005

0.257 33.09 0.205 0.425 0.3982 0.357 0.8335 6 1 0.375 1.375 12.502 6.6 1 0.328 0.748 0.005

44% 87% 100% 142% 35% 120% 120% 24% 16% 73% 105% 26% 84% 11% 91% 16% 220%

58% 85% 114% 148% 40% 175% 132% 29% 20% 88% 95% 29% 109% 17% 145% 16% 260%

340 3,304 565 7,600 445 1,800 204,396

340 3,143 717 11,539 510 1,874 307,731

0.09 0.99 0.11 0.99 0.04 0.32 38.55

0.09 1.05 0.15 1.48 0.06 0.40 49.31

0.1143 1.1728 0.164 4.9 0.109 1.48 64

0.1143 1.9628 0.164 4.9 0.109 1.48 74

77% 85% 67% 20% 40% 22%

77% 54% 88% 30% 55% 27%