WQCS00057_NOI_NOV2020DV0048_Response_#3_20200218

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City of Thomasville
Thomasville, North Carolina 27360
Lon T. Snider
Regional Supervisor
WQROS, WSRO, DWR, NCDEQ
450 W. Hanes Mill Road, Suite 300
Winston-Salem, NC 27105
RE: Notice of Intent Letter Response
Incidents Number 201901889 and 201901901
Utilities Department
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18 February 2020
Dear Mr. Snider,
In response to the letter of Notice of Intent of 03 February 2020 the City of Thomasville asks
that the following be taken into consideration:
Regarding incident # 201901889: Rainfall on the date of the event was over 1.5" throughout the
area as reflected in the attached graphs of precipitation on December 13 and 14. We are aware of and
have continued to pursue identification and remediation of I&I issues on the collection system leading
into the Rains Road pump station.
Regarding incident #201901901:ahis incident occurred after rain fell for a second period on
already saturated ground. Given the saturation already evident the additional 0.22 inches of rain that
fell entered the already full collection system and caused this overflow.
First, a recap of information previously submitted, but still relevant:
We have been and will continue to pursue identification and remediation of the sources of I&I
in a logical manner. There are two main outfalls that lead into this station, Hunts Fork Creek and Hasty
Creek.
KRG Utilities has completed cleaning and video inspection of —9,030 linear -feet of 18" and 21"
RCP pipe on the Hunts Fork Creek Outfall, one of the two main outfalls that lead into this station, at a
cost of over $80,000. Overall, the Hunts Fork Creek Outfall pipe appears to be in very good condition
for a 60-year-old concrete pipe carrying sewer. The only sources of inflow found thus far are located at
the few direct taps into this line. These will be repaired.
KRG Utilities has also completed cleaning and video inspection of the main Hasty Creek Outfall
line, 15,375 linear feet of 8" to 15" VC and DI line at a cost of $57,821.00. There are 6 segments of this
line that will require plugging and re -inspecting to complete inspection due to the high water levels
encountered. Several small sources of infiltration were identified and remediation options are being
explored.
Smoke testing of 108,447 linear -feet of these outfalls and 547 manholes leading into this
station was completed by Consulting Engineering firm Alley Williams Carmen and King and resulted in
the location and repair of 122 cleanouts. Twenty-three manholes, mostly located on the lower Hasty
Creek outfall were identified in the report as possible sources of I&I in need of attention. Manhole
rehabilitations will be scheduled pending receipt of results of additional cleaning and video inspection
currently taking place on the Hasty Creek Outfall. The entire main Hasty Creek outfall has been cleaned
and video inspected by KRG Utilities, but there were several segments of the lower Hasty Creek outfall
that could not be video inspected properly due to the volume of water in the pipes and are currently
scheduled to be plugged upstream and re -inspected by video. These segments have still not been re-

inspected due to the high volume of water in the pipes — presumably due to the high amount of
precipitation we have been experiencing. Pending the results of these inspections the determination
will be made as to if any and if so how much of the lower Hasty Creek outfall needs rehabilitation by
relining of pipes and manhole rehabilitation.
One of the sub -basins that feed into the Hasty Creek outfall has been cleaned and video
inspected and only one section of damaged pipe has been found. This pipe section, while damaged, did
not appear to be an active source of inflow, but it will be repaired now that we are aware of it. Repair
of this section of pipe will require the removal of a concrete driveway and is being scheduled.
The entire main line of the Hunt's Fork Creek outfall was cleaned and video inspected previous
to investigation of the Hasty Creek outfall due to its age (1969) and material composition (RCP) and was
found to be in surprisingly good shape. The only sources of I&I located were three or four break-in
service taps that had inflow at the connection. Contractors are currently pricing out the repair of these
service taps.
New information:
Alley Williams Carmen and King is currently performing a flow study of the entirety of the
drainage areas that discharge into both the Rains Road Pump Station and the next downstream pump
station, Northside Pump Station. Preliminary results are expected near the end of February/beginning
of March and should help us to narrow down whether the causative problem is more closely aligned
with excessive 1&I or undersized pump stations to meet the existing sewershed area demand.
The City of Thomasville has spent, and will continue to spend, millions of dollars to protect the
environment by identifying and correcting deficiencies in the collection system. There were no known
impacts to public health, fish kills, or recreational area closures as a result of these spills.
The City of Thomasville asks that the ongoing efforts and expenditures to identify and
remediate the sources of I&I in the sanitary sewer collection system be taken into account with any
enforcement actions considered.
Sincerely,
CC: Kelly Craver
Morgan Huffman
Utilities Director
City of Thomasville
336-475-4220