NC0047597_Flow Allocation Approval_20230124

January 24, 2023
Mr. Robert N. Joyner, PE
Development Review Group Manager
City of Durham, Department of Public Works
101 City Hall Plaza
Durham, N. C. 27701
Subject: City of Durham Sanitary Sewer Flow Allocations
North and South Durham Water Reclamation Facilities (NC0023841 & NC0047597)
Block Flow Approval #33
Durham County

Dear Mr. Joyner:
The Environmental Management Commission has previously approved the City of Durham's request for full
delegation authority to issue sanitary sewer extension permits. In conjunction with that delegation, this
office feels it appropriate to grant the City the approval to issue such permits based upon a block flow
approval process. Previously, the Raleigh Regional Office has granted block flow approvals for the North
Durham WRF totaling 10,000,000 GPD, and block flow approvals totaling 9,500,000 GPD for the Durham
South WRF.

As requested in your letter dated January 18, 2023, the Raleigh Regional Office hereby grants an additional
block flow allocation of 800,000 GPD for the North Durham Water Reclamation Facility, and an additional
block flow allocation of 200,000 GPD for the South Durham Water Reclamation Facility. This additional
allocation yields a total of 10,800,000 GPD granted for the North Durham WRF and 9,700,000 GPD for the
South Durham WRF. As permits are issued by the City, the wastewater flow associated with those projects
will be subtracted from the block flow allocation. When the issued permits have almost depleted the flow
allocation, the City will request that it be granted an additional allocation.

Each of these facilities has a permitted capacity of 20.0 MGD. Based upon your most recent block flow
quarterly reports for the period that ended in December 31, 2022, the North Durham WRF had a 12-Month
average of 8.56 MGD, or approximately 43% of permitted capacity, while the South Durham WRF had a 12-
month average flow of 9.66 MGD, or 48% of permitted capacity.

The Raleigh Regional Office (RRO) requires that the Town submit a report summarizing the permitting activity
by providing the following information for the permits that have been issued:

1. Permit No.
2. Permit Issue Date
3. Permit Holder
4. Name of Project
5. Permitted (Paper) Wastewater Flow of the project
6. Total Permitted (Paper) Flow issued in the Quarter
7. Summary of Activities for Violations of the Permitting Process





  
City of Durham Block Flow Allocations #33
January 24, 2023

Additionally, the report must provide the following:

1) A running total of flow allocated to the City by the Raleigh Regional Office, to Date
2) A running total of flow from permits issued, to date
3) The remaining flow in the total allocation from the Raleigh Regional Office
4) A running total of flow which has been depleted from the allocation by issued permits, but
which has not yet become tributary to the WRF (paper flow)
5) Total flow, including flow from permits issued prior to the implementation of the block flow
approval process, not yet Tributary to the WRF
6) The most recent twelve-month actual tributary flow average for the WRF

The information required above should be submitted at least quarterly by the last day of the months of April,
July, October and January. All information may be submitted via e-mail, with attachments in Word or Excel
formats. Send electronic transmittals to [e-mail] and [e-mail] and
copy [e-mail] and [e-mail].

Please be advised that the Raleigh Regional Office reserves the right to suspend this block flow approval
process if problems occur with the operation of this program or with the compliance status of the WRFs, or
any other situations that might take place which could jeopardize the successful operation of the block flow
program.

If you have any questions regarding these block flow allocations or any other matter relative to the block flow
program, flow tracking or flow tracking reconciliation process, please contact Jason Robinson via e-mail at
the addresses above.

Sincerely,

______________________________
Vanessa E. Manuel, Assistant Regional Supervisor
Water Quality Regional Operations Section
Raleigh Regional Office
Division of Water Resources, NCDEQ

Cc: [e-mail]; [e-mail]; [e-mail]
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