2013 IBT Report Final

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Charlotte-Mecklenburg Utilities Department
Annual Report on Interbasin Transfer
Calendar Year 2013

INTRODUCTION
The North Carolina Environmental Management Commission (EMC) approved Charlotte-
Mecklenburg Utility Department’s (CMUD’s) petition to increase the amount of water
transferred from the Catawba River basin to the Rocky River basin. An interbasin transfer (IBT)
Certificate was issued on March 14, 2002 that authorizes CMUD to transfer up to 33 million
gallons per day (mgd) between the river basins.

The IBT Certificate requires CMUD to report maximum daily IBT amounts annually to the North
Carolina Division of Water Resources (NC DWR) until such time as the transfer amount exceeds
80% of the authorized amount. Once that amount is exceeded, CMUD is required to report
monthly. The Charlotte-Mecklenburg Utility Department has not exceeded 80% of the
authorized IBT amount.

SYSTEM OVERVIEW
CMUD operates the water and wastewater systems that serve Charlotte, Cornelius, Davidson,
Huntersville, Mint Hill, Matthews, Pineville, and much of the unincorporated areas of
Mecklenburg County. This system is divided between two river basins designated by NC
General Statutes for regulation of IBT water. The western portion of the system is within the
Catawba River basin and the eastern portion is within the Rocky River basin. Water transferred
from the Catawba River basin to the Rocky River basin that is not returned to the Catawba river
basin is regulated IBT.

Water for distribution to CMUD’s customers is withdrawn from the Catawba River basin at two
locations. An intake at Lake Norman sends water to the Lee S. Dukes Water Treatment Plant. A
second intake at Mountain Island Lake sends water to the Walter M. Franklin Water Treatment
Plant and to the Vest Water Treatment Plant. Potable water from these three plants is
delivered through an interconnected distribution system to retail customers throughout
CMUD’s service area in Mecklenburg County and in small areas of Iredell, Cabarrus, and Union
Counties. CMUD also provides wholesale water to municipal systems for resale including: City
of Concord (NC), Town of Harrisburg (NC), Union County (NC), York County Water & Sewer
Authority (SC), and Lancaster County Water and Sewer District (SC).

CMUD treats wastewater at five advanced wastewater treatment plants (WWTP’s) that
discharge into small streams in Mecklenburg County. Four of the streams are tributary to the

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Catawba River basin and one (Mallard Creek) is tributary to the Rocky River basin. CMUD also
conveys wastewater generated in portions of Mecklenburg County to the Rocky River Regional
Wastewater Treatment Plant (RRRWWTP) operated by the Water and Sewer Authority of
Cabarrus County (WSACC). The RRRWWTP discharges treated effluent to the Rocky River.

IBT MONITORING
Water supplied to CMUD’s retail customers in the Rocky River Basin, that is not returned to the
Catawba basin, is included in the reported IBT amounts. Water provided to municipalities with
service areas in the Rocky River basin includes the City of Concord and the Town of Harrisburg.

CMUD can transfer treated potable water to the City of Concord through three metered
connections to their water system. All of Concord’s service area is within the Rocky River basin,
so any water purchased by them becomes an IBT. Water service is only provided as an
emergency back-up to Concord’s routine supply which is Lake Howell and several smaller
reservoirs. All of these reservoirs are within the Rocky River basin. Wastewater from Concord
is treated at the RRRWWTP. CMUD’s agreement with Concord is that water will be supplied to
them subject to availability and subject to regulatory constraints including IBT and Federal
Energy Regulatory Commission (FERC) limitations.

Concord received an IBT Certificate in January 2007, for the transfer of up to 10 mgd from the
Catawba River basin to the Rocky River basin. NC DWR advised CMUD that water sold to
Concord should not be applied to CMUD’s IBT amount. Concord did not purchase any potable
water from CMUD in calendar year 2012, so the IBT amounts reported do not include sales to
Concord.

CMUD can transfer treated potable water to the Town of Harrisburg through two metered
connections to their water system. Harrisburg’s service area is entirely within the Rocky River
basin and is included in CMUD’s IBT amounts.

Table 1 summarizes actual IBT amounts for calendar years 2002 through 2013 (all calculated
using the methodology approved by NC DWR in June of 2006). The table considers the daily
amounts of water transferred from the Catawba River basin to customers within the Rocky
River basin that is not returned to the Catawba River basin.

The maximum average monthly IBT for calendar year 2013 was 16.8 mgd in November, which
was approximately 50.9% of the authorized IBT of 33 mgd. The average IBT for 2013 was 12.99
mgd, approximately 39.4% of the authorized IBT. In addition to the actual amount of IBT
reported in Table 1, CMUD has committed to provide IBT to development that has been
proposed but has not yet been activated within the Rocky River basin. As of December 31,
2013, 0.63 mgd has been committed to permitted donated projects (subdivisions) that have not
been activated and 0.82 mgd was committed to master meter connections (generally

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commercial or multi-family developments) that have not been activated, both based on
maximum day estimates. The combined actual plus committed IBT for 2013 was 18.3 mgd,
approximately 55.3% of the authorized IBT.

Table 1. Actual IBT Summary
Calendar Year Avg. Annual IBT (mgd) Max. Day IBT (mgd)
2002 6.74 11.97
2003 6.91 9.82
2004 7.79 12.56
2005 8.66 13.79
2006 9.56 14.35
2007 9.96 17.22
2008 11.39 17.42
2009 12.04 16.00
2010 13.33 18.33
2011 13.11 18.82
2012 12.18 17.67
2013 12.99 16.80

COMPLIANCE WITH CERTIFICATE CONDITIONS
Condition 1: S.W.I.M. Program Summary

Mecklenburg County is required to annually summarize progress in implementation of
watershed management approaches of the Surface Water Improvement and Management
Program (S.W.I.M. program). Provided below is the summary of progress made during CY2013.
The Division of Water Resources shall have the authority to approve modifications to and need
for continued reporting as necessary.

During CY2013, watershed management approaches continued to be implemented as part
of Mecklenburg County’s S.W.I.M. Program. Efforts continued to focus on McDowell and
Goose Creeks, as initiated in 2007, as well as on the South Prong and West Branch of the
Rocky River in Davidson that began in 2009. During calendar year 2013, the following work
was completed in the three (3) watersheds:

McDowell Creek (including the Torrence Creek Tributary to McDowell Creek)

1. Completed the restoration of approximately 4,000 feet of Torrence Creek within the
business park called The Park - Huntersville.

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2. Completed the restoration of approximately 10,000 feet of the main stem of
McDowell Creek downstream of the Birkdale community in the Town of Huntersville.

3. Initiated the design process for Phase II of the stream restoration project within The
Park - Huntersville.

Goose Creek (including the Stevens Creek Tributary to Goose Creek)

1. Completed the conceptual design for the restoration of approximately two (2) miles
of Stevens Creek. Planning and property acquisition is ongoing for this project.

Rocky River

1. Received notification from the U.S. Army Corps of Engineers that the Rocky River
Watershed in Mecklenburg County was approved for a 206 Program study.

2. Continued to collaborate with the citizens and elected officials in the Town of
Davidson to identify funding to repair a significant head-cut on the grounds of
Davidson Elementary School.

Condition 2: Stakeholder Process (Completed)
A stakeholder process is required to investigate, develop, adopt, and implement storm water
ordinances that control water quantity from single-family development and water quality for all
development until completed. The requirements of Condition 2 were completed in 2007.

Condition 3: Goose Creek Subbasin (Completed)
The IBT Certificate removed the Goose Creek subbasin from the area to be served by the IBT,
and imposed a moratorium on the installation of new IBT water lines (water lines crossing the
ridgeline) into Goose Creek subbasin until the impacts of additional growth on the endangered
species were fully evaluated.
CMUD submitted the final Environmental Assessment of new development in the Goose
Creek basin (Mint Hill area) to the NC Division of Water Resources (DWR) in February of
2013. The Environmental Management Commission approved the Environmental
Assessment in May of 2013 and has removed the requirements under condition 3.

Condition 4: Environmental Management Commission
The IBT Certificate provides that the Environmental Management Commission may reopen the
Certificate under certain circumstances. This did not occur in 2013.

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Condition 5: Compliance and Monitoring Plan

The IBT Certificate requires CMUD to develop a compliance and monitoring plan for reporting
maximum daily transfer amounts, compliance with certificate conditions, and progress on
mitigation measures, and drought management activities. CMUD’s monitoring plan and
reporting format were approved in June of 2006 by NC DWR and continue to be used for 2013.

The Charlotte Mecklenburg Utility Department monitored water treatment plant pump
rates, streamflow and lake storage indicators, the US Drought Monitor, and other
factors in accordance with the CMUD Water Shortage Response Plan. Measurements
were assessed monthly to identify designated triggers that could indicate developing
drought conditions. All appropriate planning, communication and preparation were in
place to respond as needed to changing conditions.
In coordination with 17 other utilities in the Catawba-Wateree river basin, CMUD
participated in regional drought response planning and response activities as directed by
the FERC- approved Low Inflow Protocol.

SUMMARY
The actual maximum day amount of water transferred from the Catawba River basin to the
Rocky River basin was 16.8 mgd, less than 50.9% of the authorized maximum day value of 33
mgd. The combined total of actual and outstanding IBT volumes was 18.25 mgd, less than
55.3% of the authorized maximum day value. CMUD is in full compliance with IBT
authorizations and compliance conditions for calendar year 2013.