WQCS00068_NOV-2021-DV-0056 RSP_20210210

South Granville Water and Sewer Authority

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February 10, 2021
Scott Vinson, Regional Supervisor
Water Quality Regional Operations Section
Division of Water Resources, NCDEQ
1628 Mail Service Center
Raleigh, NC 27699-1628

Re: Written Response to NOV-2021-DV-0056
South Granville Water and Sewer Authority
Collection System Permit No. WQCS00068
South Granville Water and Sewer Authority (SGWASA)
Granville County

Dear Mr. Vinson:
I am writing you in response to NOV-2021-DV-0056 which included Incident Numbers: 202003497 and
202003544. SGWASA received the NOV-2021-DV-0056 notification letter from NCDEQ on January 28,
2021. A written response to your office is required within 15 business days following the receipt of the
notification. This response dated February 10, 2021 complies with that requirement. Following is an
overview and response by SGWASA to these incidents.
Incident No. 202003497 (12/16/2020): B STREET #2 PUMP STATION
The overflow at this location occurred during a prolonged, heavy rainfall event on 12/16/20. During
the wet-weather flows, the two discharge pumps at the pump station became clogged with debris,
thus causing the pumps to lose their prime, become overheated, and then shut down. The
overflow total at this location was 600 gallons, of which 600 gallons reached surface water. Crews
inspected, cleaned and applied lime to area affected.
SGWASA’s utility engineer is performing extensive analysis of the pump stations in the immediate
area to better understand what actions can be taken to eliminate these incidents from occurring in
the future. SGWASA will initiate improvements as needed to correct the situations.
SGWASA recently purchased and installed real-time flow monitoring and advance alarming
equipment from ADS Company. One of the ADS flow monitoring units will be installed at this
location, thus providing SGWASA with better information and reaction time, should the pump
station need preventative spill maintenance, etc. Additionally, SGWASA’s Utility Engineer is working
closely with the SGWASA pump station mechanics to perform additional pump runtime/drawdown
analysis to substantiate that the pumps are sized/operating correctly. If they are not, then the
pumps will be replaced/upsized, etc.
In addition, SGWASA is working with an engineering consultant to develop a comprehensive sewer
model. The system draining to the B Street #2 Lift Station has been prioritized and will be one of
the first areas fully modeled (the consultant has been directed to prioritize the B Street #2 and
Franklin Street sewer drainage areas). The creation of this sewer model will provide additional
information to better determine the necessary modifications required to eliminate future
overflows from this lift station. All these actions provide insight to SGWASA’s aggressive approach
to eliminate future sanitary sewer overflows due to either mechanical failures or I&I.
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Incident No. 202003544 (12/16/2020): 120 Franklin Street Pump Station
The overflow at this location occurred during a prolonged, heavy rainfall event on 12/16/20. The
overflow total at this location (manhole #4152) was 200 gallons, of which 200 gallons reached
surface water. Crews inspected, cleaned and applied lime to area affected.
SGWASA’s utility engineer is performing extensive analysis of the pump stations in the immediate
area to better understand what actions can be taken to eliminate these incidents from occurring in
the future. SGWASA will initiate improvements as needed to correct the situations.
Like the location above, one of the ADS flow monitoring units will be installed at this location, thus
providing SGWASA with better information and reaction time, should the pump station need
preventative spill maintenance, etc. Additionally, SGWASA’s Utility Engineer is working closely with
the SGWASA pump station mechanics to perform additional pump runtime/drawdown analysis to
substantiate that the pumps are sized/operating correctly. If they are not, then the pumps will be
replaced/upsized, etc.
In addition, SGWASA is working with an engineering consultant to develop a comprehensive sewer
model. The system draining to the Franklin Street Lift Station has been prioritized and will be one
of the first areas fully modeled (the consultant has been directed to prioritize the B Street #2 and
Franklin Street sewer drainage areas). The creation of this sewer model will provide additional
information to better determine the necessary modifications required to eliminate future
overflows from this lift station. All these actions provide insight to SGWASA’s aggressive approach
to eliminate future sanitary sewer overflows due to either mechanical failures or I&I.
In general, based on a review of the weather conditions and site conditions observed by staff on initial
arrival to these overflows SGWASA submits that these discharges were unintentional, temporary and
caused by factors beyond the reasonable control of SGWASA and could not have been prevented by the
exercise of reasonable control.
Asset Management/CIP Projects to Mitigate Future Overflows
During the past year SGWASA invested in a new asset management/work management program to better
manage maintenance activities for SGWASA’s utility assets, improve customer service, and provide
forecasts of needed future capital improvement projects. The asset management program, presently in its
initial stages of implementation, will help SGWASA to be more proactive in sanitary sewer maintenance,
including cleaning, televising, root cleaning, pipe repairs, Inflow and Infiltration (I&I) investigations/follow
up, etc.
In addition to the new asset management/work management program, SGWASA is also building a hydraulic
model for the wastewater collection system. The hydraulic model is assisting SGWASA with a better
understanding of hydraulic conditions and restrictions throughout the collection system. Furthermore, the
hydraulic model is assisting SGWASA in identifying priority projects, such as pipe replacements, pump
station upgrades, manhole repairs, I&I problems, etc.
This past year, SGWASA also invested in professional engineering assistance in developing an I&I
issues/mitigation strategy across the sanitary sewer system. These proposed I&I studies, although limited in
scope presently, are focused on areas that are causing issues with overflows, such as those highlighted
above. To enhance these efforts, SGWASA recently purchased real-time flow monitoring and advance
alarming equipment, plus a real-time rain gauge, from the ADS Company. These units are being deployed
throughout the SGWASA service area in critical areas. These units will provide SGWASA with real-time flow
monitoring and alerting of staff prior to collection system overflows.
Based on the information contained in this letter, I believe it is apparent to the NCDEQ - Division of Water
Resources, that SGWASA is actively, and aggressively pursuing system-wide improvements to the sanitary
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sewer collection system. Please take this into account as you determine what actions you will be taking
regarding the sanitary sewer overflows that have occurred, as outlined above.

I look forward to discussing this information further with you. Please contact me at your convenience.
Sincerely,
Scott N. Schroyer
Scott N. Schroyer, Executive Director
South Granville Water and Sewer Authority (SGWASA)
415 Central Avenue, Suite B.
Butner, NC 27509
919-575-3367 Ext. 312
[e-mail]

Cc: Fred Dancy, SGWASA Utility Operations Director
Jon Mase, Distribution and Collection System Superintendent
Robert Jackson, Distribution and Collection System Supervisor
Mark Hamlett, PE Utility Engineer-Manager