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Chapter 14
Water Resources
14.1 River Basin Hydrologic Units
Under the federal system, the French Broad River basin is made up of hydrologic areas referred
to as cataloging units (USGS 8-digit hydrologic units). The French Broad River basin is made
up of three whole cataloging units: the Upper French Broad River, Pigeon River and Nolichucky
River. Cataloging units are further divided into smaller watershed units (14-digit hydrologic
units or local watersheds) that are used for smaller scale planning like that done by NCEEP
(Section 16.3). There are 89 local watershed units in the basin. Table 24 compares the three
systems. A map identifying the hydrologic units and subbasins can be found in Appendix I.
Table 24 Hydrologic Subdivisions in the French Broad River Basin
Watershed Name
and
Major Tributaries
DWQ
Subbasin
6-Digit
Codes
USGS
8-Digit
Hydrologic
Units
USGS
14-Digit Hydrologic Units
Local Watersheds*
Upper French Broad River
East Fork French Broad River
North Fork French Broad River
West Fork French Broad River
Little River
Cane Creek
Hominy Creek
Mud Creek
Sandymush Creek
Swannanoa River
Davidson River
Mills River
Big Ivy Creek (River)
Big Laurel Creek
Spring Creek
04-03-01
04-03-02
04-03-03
04-03-04
06010105
070010, 010010, 010020, 010030, 010040, 010050,
010055, 010060, 010080, 020010, 030010, 030020,
030030, 030040, 040010, 040020, 050010, 060010,
060020, 060030, 070020, 070030, 070040, 080010,
080020, 080030, 090010, 090020, 090030, 090040,
010070, 020015, 020020, 020030, 080040, 100010,
100020, 100030, 100040, 110010, 110020, 110030,
110040, 110050, 120010, 120020, 120030, 120040,
130010, 130020, 130030, 130040, 140010
Pigeon River
East Fork Pigeon River
West Fork Pigeon River
Big Creek
Cataloochee Creek
Jonathan Creek
Richland Creek
04-03-05
06010106
010010, 010020, 010030, 010040, 020010, 020020,
020030, 020040, 020050, 020060, 020070, 030010,
030020, 030030, 030040
Nolichucky River
Big Rock Creek
North Toe River
South Toe River
Cane River
04-03-06
04-03-07
06010108 010010, 010020, 010030, 010040, 020010, 020020,
020030, 030010, 040010, 050010, 060010, 060020,
100010, 100020, 100030, 120010, 070010, 080010,
080020, 080030, 080040
* Numbers from the 8-digit and 14-digit column make the full 14-digit HU. Example: 06010105070010 is one 14-digit HU.
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14.2 Minimum Streamflow
One of the purposes of the Dam Safety Law is to ensure maintenance of minimum streamflows
below dams. Conditions may be placed on dam operations specifying mandatory minimum
releases in order to maintain adequate quantity and quality of water in the length of a stream
affected by an impoundment. The Division of Water Resources (DWR), in conjunction with the
Wildlife Resources Commission (WRC), recommends conditions relating to release of flows to
satisfy minimum instream flow requirements. The Division of Land Resources (DLR) issues the
permits. The Federal Energy Regulatory Commission (FERC) licenses all dams associated with
hydropower.
Hydroelectric Dams
There are five operational dams in the French Broad River basin, including three on the French
Broad River, one on Ivy Creek, and one on the Pigeon River. Information on each of these dams
is presented below.
Craggy Dam is required by FERC to provide a tiered release of 460 cfs from July through
January, and 860 cfs the remainder of the year. This dam operates in a run-of-river (non-
peaking) mode and bypasses 3,200 feet of natural channel. It is located just downstream of the
Beaverdam Creek confluence, and the facility is owned and operated by Buncombe County
Metropolitan Sewer District.
Capitola Dam has no minimum release requirement according to their FERC license. This dam
operates in a run-of-river (non-peaking) mode and bypasses 1,000 feet of natural channel. It is
located just upstream of Marshall, and the facility is owned and operated by the French Broad
Electric Membership Corporation.
Redmon Dam has no minimum release requirement according to their FERC license. The dam is
operates in a run-of-river (non-peaking) mode and has no bypass stream channel. It is located
just downstream of Marshall and the facility is owned and operated by Progress Energy.
Ivy River (Creek) Dam is located in AU# 6-96-(11.7). This facility is required by FERC to
provide a 7Q10 flow of 16 cfs. A calibrated gage is required to monitor downstream flows. This
dam operates in a run-of-river (non-peaking) mode and has no bypass channel. It is located 2.2
miles upstream of the mouth of Ivy Creek and is owned by Sithe Energies, Inc.
The Walters hydroelectric facility is located in AU# 5-(7) and is operated by Progress Energy.
This facility is required by FERC to provide a minimum flow of 100 cfs one mile below the
powerhouse at Brown’s Bridge in Tennessee. A gage is required at Brown’s Bridge to monitor
flows. From the dam to the powerhouse, the facility bypasses 12 miles of natural channel. The
powerhouse is located at the Pigeon River confluence with Big Creek on the North Carolina-
Tennessee border.
Scheduled recreational releases are also required at Walters. The Schedule One recreational
release is 1,200 cfs from 1:00 pm to 6:00 pm on two weekdays during each week, and 12:00 pm
to 6:00 pm on Saturdays between the Saturday of the Memorial Day weekend and the Saturday
of the Labor Day weekend. The Schedule Two recreational release is 1,200 cfs from 2:00 pm to
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6:00 pm on not less than three weekdays per week during the two weeks prior to the Memorial
Day weekend and the two weeks after the Labor Day weekend. The release schedule may be
modified based on recreational use. The utility is to provide a toll-free phone number to provide
information on the recreational flow releases.
No minimum release will be required in the bypassed natural channel until water quality and
biological criteria are met. In lieu of a minimum flow, the utility will contribute funds to the
Pigeon River Fund (www.pigeonriverfund.org) that will be administered by the Pigeon River
Committee. In exchange for contributions to the fund, the Secretary of DENR will not seek a
minimum release from the dam for ten years. When water quality and biological criteria are met,
the established minimum release into the bypassed channel will be 30 cfs during May and June,
and 20 cfs during the remainder of the year.
The Cascade Power Company surrendered the license to operate the Cascade hydroelectric
facility on the Little River [AU# 6-38-(1)]. During operation, the facility was required to
provide a 7Q10 flow of 23 cfs below the dam. A calibrated gage was established to monitor the
flow requirement. The dam release was required to provide water in a run-of-river mode, and it
bypassed 1,016 feet of natural stream channel when in operation.
Lake Junaluska located on Richland Creek [AU# 5-16-(16)] previously was a hydroelectric dam.
In 1995, The Lake Junaluska Assembly surrendered its license exemption to produce power to
FERC. The Assembly is still required to release water from the dam in a run-of-river mode. The
Assembly agreed to a lake management plan with the NC Wildlife Resources Commission that
allows the lake to be drawn down beginning on November 15 to a level not to exceed 2,448 feet
mean sea level and return to full pool by April 15. A 7Q10 flow of 27.7 cfs or inflow, whichever
is less, should be maintained below the dam during refill.
Water Supply Impoundments, Withdrawals and/or Miscellaneous Dams
There are additional impoundments that are not licensed hydroelectric dams in this basin. The
following are water supply impoundments, withdrawals and/or miscellaneous dams.
The Town of Waynesville’s water supply reservoir is located on Allen Creek
[AU# 5-16-7-(8.5)]. The dam has a 7Q10 release requirement of 3.5 cfs. A
calibrated flume is used to make the release.
On the Little East Fork Pigeon River [AU# 5-2-12-(5.5)] a trout hatchery is
permitted to withdraw water only when 6.5 cfs is maintained downstream of the
point of withdrawal. A calibrated gage is required to monitor flows.
A trout hatchery diversion on Shope Creek (AU# 6-78-3) was permitted with an
installed orifice sized for a 7Q10 release of 0.28 cfs.
Long Valley Lake on Long Valley Branch (AU# 6-75) has a flow requirement of
0.36 cfs.
Eagle Lake Dam on Phillips Creek (AU# 6-26-1) has a flow requirement of 0.5
cfs.
Cove Dam on an unnamed tributary of Swannanoa River near Oteen has a flow
requirement of 0.2 cfs.
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Instream Flow Studies
The Division of Water Resources (DWR) participated in several instream flow studies during
this cycle in the French Broad River basin. The studies and their findings are described below.
DWR conducted an instream flow study on Jonathan Creek [AU# 5-26-(5.5) and 5-26-(7)].
DWR along with the NC Wildlife Resources Commission (WRC) and the Maggie Valley
Sanitary District reviewed a proposal for an expansion of the water treatment plant from 1.5
MGD to 3.0 MGD. The withdrawal from Jonathan Creek could increase to 3.0 MGD if an 8 cfs
flow is maintained downstream of the intake. The installation of a calibrated gage will be
required with this expansion, and withdrawal from Campbell Creek [AU# 5-26-8-(2.5)] would
remain unchanged.
DWR, the WRC, and the City of Hendersonville participated in an instream flow study for Mills
River [AU# 6-54-(4.5) and 6-54-(5)]. The study was the result of a proposal to relocate the city’s
water intake upstream of Highway 191/280. The study found that the city could withdraw 12
MGD without restriction, but withdrawals up to a maximum of 24 MGD would require a
minimum flow of 30 cfs.
Further analysis examining the net habitat benefits was conducted for the city’s proposal for a
plant capacity of 18 MGD. This study indicated that the city could withdraw up to 18 MGD
without restrictions in January through June, with an 8 cfs release from the upstream
impoundments on North Fork Mills River and Bradley Creek. If there were no withdrawals from
the upstream impoundments, then up to 14.2 MGD could be withdrawn in July through
December without restrictions. In July through December, withdrawals up to 18 MGD were
permissible if North Fork Mills River and Bradley Creek ran free, and the following targets were
met below the downstream intake: 30 cfs (July and December); 40 cfs (August, October and
November); and 42 cfs (September). Hendersonville must establish a gage downstream of their
intake to monitor flows when their maximum daily withdrawal equals or exceeds 14 MGD.
Anticipating events that may temporarily prevent the use of the downstream source, such as in
the event of a spill, the upstream impoundments may be used at any time. Conservation efforts
or interconnection purchases should be used to maintain the 8 cfs downstream requirement.
During storms, if nonpoint contaminants prevent use of the downstream source, the upstream
impoundments may be used as long as the 8 cfs downstream flow can be maintained and more
than 160 cfs (mean annual flow) is maintained at the US Geological Survey gage (#03446000).
The City of Hendersonville uses impoundments on North Fork Mills River [AU# 6-54-2-(1)] and
Bradley Creek [AU# 6-54-3-17-(0.5)] as water supply sources. The city withdraws a combined
volume of 5.5 MGD on average. The DWR participated in a study on these waters with the NC
WRC, the US Department of Agriculture-Forest Service, and the City of Hendersonville. The
study was used, in part, to issue a special use permit for Hendersonville from the U.S. Forest
Service. All parties agreed upon an 8 cfs release below each of the water supply impoundments
with gages to monitor the releases.
Chapter 14 – Water Resources 130
14.3 Interbasin Transfers
In addition to water withdrawals (discussed above), water users in North Carolina are also
required to register surface water transfers with the Division of Water Resources (DWR) if the
amount is 100,000 gallons per day or more. In addition, persons wishing to transfer two million
gallons per day (MGD) or more, or increase an existing transfer by 25 percent or more, must first
obtain a certificate from the Environmental Management Commission (G.S. 143-215.22I). The
river basin boundaries that apply to these requirements are designated on a map entitled Major
River Basins and Sub-Basins in North Carolina, on file in the Office of the Secretary of State.
These boundaries differ from the 17 major river basins delineated by DWQ. Table 25
summarizes interbasin transfers within the French Broad River basin.
In determining whether a certificate should be issued, the state must determine that the overall
benefits of a transfer outweigh the potential impacts. Factors used to determine whether a
certificate should be issued include:
• The necessity, reasonableness and beneficial effects of the transfer;
• The detrimental effects on the source and receiving basins, including effects on water supply
needs, wastewater assimilation, water quality, fish and wildlife habitat, hydroelectric power
generation, navigation and recreation;
• The cumulative effect of existing transfers or water uses in the source basin;
• Reasonable alternatives to the proposed transfer; and
• Any other facts and circumstances necessary to evaluate the transfer request.
A provision of the interbasin transfer law requires that an environmental assessment or
environmental impact statement be prepared in accordance with the State Environmental Policy
Act as supporting documentation for a transfer petition. For more information on interbasin
transfers, visit the website at http://www.ncwater.org or call DWR at (919) 733-4064.
Table 25 Estimated Interbasin Transfers in the French Broad River Basin (1997)
Supplying
System
Receiving
System
Source
Subbasin
Receiving
Subbasin
Estimated
Transfer (MGD)
Hendersonville Hendersonville French Broad River Broad River <0.1
Hendersonville Saluda French Broad River Broad River 0.151
14.4 Water Quality Issues Related to Drought
Water quality problems associated with rainfall events usually involve degradation of aquatic
habitats because the high flows may carry increased loadings of substances like metals, oils,
herbicides, pesticides, sand, clay, organic material, bacteria and nutrients. These substances can
be toxic to aquatic life (fish and insects) or may result in oxygen depletion or sedimentation.
During drought conditions, these pollutants become more concentrated in streams due to reduced
flow. Summer months are generally the most critical months for water quality. Dissolved
oxygen is naturally lower due to higher temperatures, algae grow more due to longer periods of
sunlight, and streamflows are reduced. In a long-term drought, these problems can be greatly
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exacerbated, and the potential for water quality problems to become catastrophic is increased.
This section discusses water quality problems that can be expected during low flow conditions.
The frequency of acute impacts due to nonpoint source pollution (runoff) is actually minimized
during drought conditions. However, when rain events do occur, pollutants that have been
collecting on the land surface are quickly delivered to streams. When streamflows are well
below normal, this polluted runoff becomes a larger percentage of the water flowing in the
stream. Point sources may also have water quality impacts during drought conditions even
though permit limits are being met. Facilities that discharge wastewater have permit limits that
are based on the historic low flow conditions. During droughts, these wastewater discharges
may make up a larger percentage of the water flowing in a stream than during normal climatic
and streamflow conditions. These discharges may also contribute to lowered dissolved oxygen
concentrations and increased levels of other pollutants during drought conditions.
As streamflows decrease, there is less habitat available for aquatic insects and fish, particularly
around lake shorelines. There is also less water available for irrigation and for water supplies.
The dry conditions and increased removal of water for these uses further increases strain on the
resource. With lesshabitat, naturally lower dissolved oxygen levels and higher water
temperatures, the potential for large kills of fish and aquatic insects is very high. These
conditions may stress the fish to the point where they become more susceptible to disease and
where stresses that normally would not harm them result in mortality.
These are also areas where longer retention times due to decreased flows allow algae to take full
advantage of the nutrients present resulting in algal blooms. During the daylight hours, algae
greatly increase the amount dissolved oxygen in the water, but at night algal respiration and die
off can cause dissolved oxygen levels to drop low enough to cause fish kills. Besides increasing
the frequency of fish kills, algae blooms can also cause difficulty in water treatment resulting in
taste and odor problems in finished drinking water.
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