HomeMy WebLinkAboutRequest for Additional Information, Lake Lure Dam Drain Gate & Test Borings for Dam Replacement, Rutherford County (DWR #20230215)1
Winston, Joey
From:Winston, Joey
Sent:Tuesday, April 4, 2023 8:29 AM
To:gerald@mogmit.com
Cc:whperkins@townoflakelure.com; mdydula@townoflakelure.com; bstepek@schnabel-eng.com;
Brandee.C.Boggs@usace.army.mil; Leslie, Andrea J
Subject:Request for Additional Information, Lake Lure Dam Drain Gate & Test Borings for Dam Replacement,
Rutherford County (DWR #20230215)
Mr. Pottern,
On February 8, 2022, the Division of Water Resources (Division) received your application requesting a 401 Water
Quality Certification from the Division for the subject project. The Division has determined that your application is
incomplete and cannot be processed. The application is on‐hold until all of the following information is received:
1. Please provide plans, with dimensions, for the following impacts described in the application: the temporary
access road and culverts, the new dam drain gate, and an example accessway for the geotechnical test borings.
The Division requires plans of all proposed impacts to determine the project’s effects on water quality. [15A
NCAC 02H .0502(a)(9); 15A NCAC 02H .0506(b)]
2. Please provide a construction sequence and timeline for the installation and removal of the temporary access
road, including a discussion of the measures taken to ensure water quality standards will be met throughout the
process. Please include any necessary details with project plans. [15A NCAC 02H .0502(a)(4); 15A NCAC 02H
.0502(a)(9); 15A NCAC 02H .0506(b)(2)]
3. Please provide a construction sequence and timeline for the installation of the dam drain gate, including a
discussion of the measures taken to ensure water quality standards will be met throughout the process. The
Division does not allow uncured or curing concrete to come in contact with surface waters; please include in the
discussion measures taken to prevent this. Please include any necessary details with project plans. [15A NCAC
02H .0502(a)(4); 15A NCAC 02H .0502(a)(9); 15A NCAC 02H .0506(b)(2)]
4. Please provide a discussion of how the drain gate will be operated, including the frequency of discharge, and
how it will impact the water quality downstream of the dam. The source of the discharge is indicated to be near
the lake bottom, where water is naturally colder and has lower oxygen levels. Please provide reasonable
assurance that the gate will not be operated in a way that will cause a water quality violation. [15A NCAC 02H
.0502(a)(4); 15A NCAC 02H .0506(b)(2)]
5. Please provide a discussion of the design choices made regarding turbidity and sedimentation. Sediment has the
potential to accumulate at the base of dams, where the new drain gate is proposed. Please include in the
discussion measures taken to ensure the gate will not release sediment from the lake bottom when it is
operated. If available, please also include any bathymetric surveys that indicate the sediment depth at the
location of the proposed drain gate. The drain gate is also expected to release high velocity flow when opened.
Please include in the discussion measures taken to prevent erosion and sedimentation on the downstream side
of the gate. [15A NCAC 02H .0502(a)(4); 15A NCAC 02H .0506(b)(2); 15A NCAC 02H .0506(b)(3)]
6. Please provide a construction sequence and timeline for the installation and removal of the temporary
accessways for the geotechnical test borings, including a discussion of the measures taken to ensure water
quality standards will be met throughout the process. Please include further discussion of how wastewater from
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the drilling operation will be contained and removed from the site. Please include any necessary details with
project plans. [15A NCAC 02H .0502(a)(4); 15A NCAC 02H .0502(a)(9); 15A NCAC 02H .0506(b)(2)]
Pursuant to Title 15A NCAC 02H .0502(c), the applicant shall furnish all of the above requested information for the
proper consideration of the application. Please provide your response by May 5, 2023. If all of the requested
information is not received, the Division will be unable to approve the application and it will be denied as incomplete.
The denial of this project will necessitate reapplication to the Division for approval, including a complete application
package and appropriate fee.
Please let me know if you have any questions.
Regards,
Joey
Joey Winston
Environmental Specialist I, Division of Water Resources
North Carolina Department of Environmental Quality
Office: (828) 296‐4685 | Cell: (828) 785‐9171
joey.winston@ncdenr.gov