NCS000494_Lewisville Self Audit_20201204

MUNICIPAL SEPARATE STORM SEWER SYSTEM (MS4)
PROGRAM SELF -AUDIT REPORT
NPDES PERMIT NO. NCS000494
LEWISVILLE, NORTH CAROLINA
6510 Shallowford Rd.
Self -Audit Date: September 1, 2020 — December 1, 2020
Report Date: December 1, 2020
North Carolina Department of Environmental Quality
Division of Energy, Mineral & Land Resources Stormwater Program
512 N. Salisbury Street, 9th floor
1612 Mail Service Center
Raleigh, NC 27699-1612

MS4 Permit Self -Audit Report
Lewisville, NC: NPDES Permit No. NCS000494
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Audit Date: September 1, 2020 — December 1, 2020 i

MS4 Permit Self -Audit Report
Lewisville, NC: NPDES Permit No. NCS000494
Self -TABLE OF CONTENTS
Self -Audit Details .................................
Permittee Information .........................
Supporting Documents ........................
Post -Construction Site Runoff Controls
DISCLAIMER
44
This audit consists of an evaluation of program compliance with the issued permit and implementation of
the approved Stormwater Management Plan. This audit report does not include a review of all program
components, and program deficiencies in addition to those noted may be present. The permittee is
required to assess program progress and permit compliance, and to implement the approved Stormwater
Management Plan in accordance with the issued permit.
Audit Date: September 1, 2020 — December 1, 2020 ii

MS4 Permit Self -Audit Report
Lewisville, NC: NPDES Permit No. NCS000494
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Audit Date: September 1, 2020 — December 1, 2020iii

MS4 Permit Self -Audit Report
Lewisville, NC: NPDES Permit No. NCS000494
Self -Audit Details
Audit ID Number:
Audit Date(s):
NCS000424—Town of Lewisville MS4 Self Audit
September 1, 2020 — December 1, 2020
Minimum Control Measures Evaluated:
❑ Program Implementation, Documentation & Assessment
❑ Public Education & Outreach
❑ Public Involvement & Participation
❑ Illicit Discharge Detection & Elimination
❑ Construction Site Runoff Controls — No delegated Sediment and Erosion Control Program
❑ Construction Site Runoff Controls — Delegated Sediment and Erosion Control Program
❑X Post -Construction Site Runoff Controls
❑ Pollution Prevention and Good Housekeeping for Municipal Operations
❑ Total Maximum Daily Loads (TMDLs)
Field Site Visits:
❑ Municipal Facilities. Number visited: Choose an item.
❑ MS4Outfalls. Number visited: Choose an item.
❑ Construction Sites. Number visited: Choose an item.
❑ Post -Construction Stormwater Runoff Controls. Number visited: Choose an item.
❑ Other: Number visited: Choose an item.
❑ Other: Number visited: Choose an item.
Inspector(s) Conducting Audit
Name, Title
Organization
Lindsey Lengyel, Water Resources Manager
Blue Stream Environmental
Audit Report Author:
Date:
Signature
12/1 /2020
Audit Report Author:
Date
Signature
Self -Audit Date(s): September 1, 2020 — December 1, 2020 Page 1 of 8

MS4 Permit Self -Audit Report
Lewisville, NC: NPDES Permit No. NCS000494
Permittee Information
MS4 Permittee Name:
Town of Lewisville
Permit Effective Date:
2/20/2017
Permit Expiration Date:
2/19/2022
City, State, ZIP: Lewisville, NC 27023
Date of Last MS4 Inspection/Audit:
7/27/2020
Co-permittee(s), if applicable: N/A
Permit Owner of Record: Town of Lewisville
Primary MS4 Representatives Participating in Audit
Name, Title
Organization
Ryan Moser, Public Works Director
Town of Lewisville
MS4 Receiving Waters
Waterbody
Classification
Impairments
Yadkin River
WS-IV
Fecal Coliform (recreation)
Mill Creek
WS-IV
None listed
Shallow Ford Lakes
WS-IV
None listed
Panther Creek
C
None listed
Double Creek
C
None listed
Blacks Creek
WS-IV
None listed
Ellison Creek
C
None listed
Ellison Creek
WS-IV
None listed
Blanket Creek
C
None listed
Reynolds Creek
C
Ecological/biological integrity benthos
Self -Audit Date(s): September 1, 2020 — December 1, 2020 Page 2 of 8

MS4 Permit Self -Audit Report
Lewisville, NC: NPDES Permit No. NCS000494
Supporting Documents
Item
Number
Document Title
When Provided
(Prior to/During/After)
1
Lewisville Comprehensive Stormwater Management Plan
After
2
Stormwater Assessment 2018
After
3
Stormwater Assessment 2019
After
4
Chapter C, Article III — Phase II Stormwater Management Ordinance
After
5
Lewisville — Stantec Stormwater Review Contracts 2017-2020
After
6
0&M Agreement — Blank
After
7
Recreation Center Bioretention Device
After
8
Recreation Center Biocell
After
Self -Audit Date(s): September 1, 2020 — December 1, 2020 Page 3 of 8

MS4 Permit Self -Audit Report
Lewisville, NC: NPDES Permit No. NCS000494
Post -Construction Site Runoff Controls
Staff Interviewed: Ryan Moser, Public Works Director
(Name, Title, Role) David Matthews, Maintenance Technician
Implementation (check all that apply):
❑X The permittee implements the components of this minimum measure.
❑ The permittee relies upon another entity to implement the components of this minimum measure: name of entity
❑X The permittee implements the following deemed -compliant program(s), which meet NPDES MS4 post -construction
requirements for the areas where implemented and in compliance with the specific program requirements as provided in 15A
NCAC and noted below (Complete Session Law 2006-246 section below):
❑ Water Supply Watershed I (WS-1) —15A NCAC 213.0212
❑ Water Supply Watershed II (WS-11) — 15A NCAC 213.0214
❑ Water Supply Watershed III (WS-III) — 15A NCAC 213.0215
© Water Supply Watershed IV (WS-IV) — 15A NCAC 213.0216
❑ Freshwater High Quality Waters (HQW) —15A NCAC 2H .1006
❑ Freshwater Outstanding Resource Waters (ORW) —15A NCAC 2H .1007
❑ Neuse River Basin Nutrient Sensitive (NSW) Management Strategy — 15A NCAC 2B .0235
❑ Tar -Pamlico River Basin Nutrient Sensitive (NSW) Management Strategy —15A NCAC 2B .0258
❑ Randleman Lake Water Supply Watershed Nutrient Management Strategy — 15A NCAC 2B .0251
❑ Universal Stormwater Management Program —15A NCAC 2H .1020
Ordinance(s) (check all that apply):
The permittee utilizes the following ordinances and/or regulatory authority to fulfill post construction minimum measure program
requirements throughout the MS4 permitted area (check all that apply):
❑ DEQ model ordinance
❑X MS4 designed post -construction practices that meet or exceed 15A NCAC 02H .1000.
❑ DEQ approved comprehensive watershed plan
❑ DEQ approved ordinance for a deemed -compliant Program (see list above)
Instructions:
For MS4s not implementing a S.L. 2006-246 deemed -compliant program, complete only the Permit Citation section below.
For MS4s implementing a S.L. 2006-246 deemed -compliant program, complete the Session Law 2006-246 section below. If the MS4
does not implement a deemed -compliant program throughout the entire MS4 permitted area, then complete the Permit Citation
section below for the permitted area(s) not covered under the S.L. 2006-246 deemed -compliant program.
Self -Audit Date(s): September 1, 2020 — December 1, 2020 Page 4 of 8

MS4 Permit Self -Audit Report
Lewisville, NC: NPDES Permit No. NCS000494
Post -Construction Site Runoff Controls
Session Law 2006-
Program Requirement
Status
supporting
246
Doc No.
Deemed -Compliant
The permittee implements deemed -compliant Program requirements in
Program(s)
accordance with the applicable 15A NCAC rules.
Yes
1
The permittee implements deemed -compliant Program requirements throughout
the entire MS4 area (If not, also complete the Permit Citation section below.)
Yes
1
The permittee applies deemed -compliant Program requirements to all federal,
state and local government projects within the permitted MS4 area who do not
Yes
1
have their own NPDES stormwater permit.
The permittee included deemed -compliant Program reporting in their MS4 Annual
Reports.
Partial
2,3
The permittee included deemed -compliant Program implementation in their
Stormwater Management Plan.
Yes
Comments
Permit Citation
Program Requirement
Status
Supporting
Doc No.
II.F.2.a
The permittee maintained an ordinance or other regulatory mechanism designed
Legal Authority
to meet the objectives of the Post -Construction Site Runoff Controls Stormwater
Yes
Management Program.
If yes, the ordinance applies throughout the corporate limits of the permittee
(Verify permit coverage area listed in Part I.D of permit and modify
Yes
accordingly).
The permittee has the authority to review designs and proposals for new
development and redevelopment to determine whether adequate stormwater
Yes
4
control measures will be installed, implemented, and maintained.
The permittee has the authority to request information such as stormwater plans,
inspection reports, monitoring results, and other information deemed necessary to
evaluate compliance with the Post -Construction Stormwater Management
Yes
4
Program.
The permittee has the authority to enter private property for the purpose of
inspecting at reasonable times any facilities, equipment, practices, or operations
Yes
4
related to stormwater discharges.
Comments
I I. F.2. b
Stormwater Control
The permittee utilizes strategies which include SCMs appropriate for the MS4.
Yes
4
Measures (SCMs)
SCMs comply with 15A NCAC 02H .1000.
Yes
4
Self -Audit Date(s): September 1, 2020 — December 1, 2020 Page 5 of 8

MS4 Permit Self -Audit Report
Lewisville, NC: NPDES Permit No. NCS000494
Post -Construction Site Runoff Controls
Comments
II.F.2.c
The permittee conducted site plan reviews of all new development and
Plan Reviews
redeveloped sites that disturb greater than or equal to one acre (including sites
that disturb less than one acre that are part of a larger common plan of
Yes
development or sale).
If yes, the site plan reviews addressed how the project applicant meets the
performance standards.
Yes
6
If yes, the site plan reviews addressed how the project will ensure long-term
Yes
6
maintenance.
Comments
II.F.2.d
The permittee maintained an inventory of projects with post -construction
Inventory of Projects
structural stormwater control measures installed and implemented at new
No
---
development and redeveloped sites.
The inventory included both public and private sector sites located within the
permittee's corporate limits that are covered by its post -construction ordinance
No
---
requirements.
Comments
II.F.2.e
The permittee provided mechanisms such as recorded deed restrictions and
Deed Restrictions
protective covenants that ensure development activities will maintain the project
No
---
and Protective
consistent with approved plans.
Covenants
Comments
II.F.2.f
The permittee implemented or required an operation and maintenance plan for
Mechanism to
the long-term operation of the SCMs required by the program.
Yes
4
Require Long-term
Operation and
The operation and maintenance plan required the owner of each SCM to perform
Maintenance
and maintain a record of annual inspections of each SCM.
Yes
4
Annual inspection of permitted structural SCMs are required to be performed by a
qualified professional.
Yes
4
Comments:
Self -Audit Date(s): September 1, 2020 — December 1, 2020 Page 6 of 8

MS4 Permit Self -Audit Report
Lewisville, NC: NPDES Permit No. NCS000494
Post -Construction Site Runoff Controls
II.F.2.g
The permittee conducted and documented inspections of each project site covered
Inspections of
under performance standards, at least one time during the permit term (Verify this
No
---
Structural
is a permit condition in Part II.F.2.g of permit and modify accordingly).
Stormwater Control
Before issuing a certificate of occupancy or temporary certificate of occupancy, the
Measures
permittee conducted a post -construction inspection to verify that the permittee's
performance standards have been met or a bond is in place to guarantee
Not
Applicable
com pl etion (Verify this is a permit condition in Part II.F.2.g of permit and modify
accordingly.
The permittee developed and implemented a written inspection program for SCMs
installed pursuant to the post -construction program(Verify this is a permit
No
---
condition in Part II.F.2.g of permit and modify accordingly.
The permittee documented and maintained records of inspections.
No
---
The permittee documented and maintained records of enforcement actions.
No
---
Comments
Certificates of occupancy are issued by the City of Winston-Salem and not the Town of Lewisville
II.F.2.h
The permittee made available through paper or electronic means, ordinances,
Educational
post -construction requirements, design standards checklists, and other materials
Materials and
appropriate for developers.
Training for
Note: New materials may be developed by the permittee, or the permittee may use
Yes
Website
Developers
materials adopted from other programs and adapted to the permittee's new
development and redevelopment program.
Comments
II.F.2.i Enforcement
The permittee tracked the issuance of notices of violation and enforcement
actions.
No
---
If yes, the tracking mechanism included the ability to identify chronic violators
Choose
for initiation of actions to reduce noncompliance.
an item.
Comments
II.F.3.b
The permittee fully complies with post construction program requirements on its
New Development
own publicly funded construction projects.
Yes
7, 8
Comments
Self -Audit Date(s): September 1, 2020 — December 1, 2020 Page 7 of 8

MS4 Permit Self -Audit Report
Lewisville, NC: NPDES Permit No. NCS000494
Post -Construction Site Runoff Controls
II.F.3.c
Does the MS4 have areas draining to Nutrient Sensitive Waters (NSW) pursuant to
Nutrient Sensitive
15A NCAC 02H .0150?
No
Waters
If yes, does the permittee use SCMs that reduce nutrient loading in order to
Choose
meet local program requirements.
an item.
If yes, does the permittee also still incorporate the stormwater controls
Choose
required for the project's density level.
an item.
If yes, does the permittee also require documentation where it is not feasible to
Choose
use SCMs that reduce nutrient loading.
an item.
Comments
II.F.3.d
The permittee ensured that the design volumes of SCMs take into account the
Design Volume
runoff at build out from all surfaces draining to the system.
No
Where "streets" convey stormwater, the permittee designed SCMs to be sized to
treat and control stormwater runoff from all surfaces draining to the SCM including
No
streets, driveways, and other impervious surfaces.
Comments
Self -Audit Date(s): September 1, 2020 — December 1, 2020 Page 8 of 8