Public Meeting Minutes
Ivey’s Pond and Dam Enhancement Project
City Project #: 671-06-004
September 20, 2010
6:00 PM
Attendants
Christopher Fleck (CF), Consulting engineer with Dewberry
Greg Cole (GC), CMSWS Project Manager
Amy Bice (AB), CMSWS Watershed Area Manager
John Schrum (JS), CMSWS Senior Water Quality Engineer
Residents
6 residents (4 households)
Meeting Started @ 6:10 (residence continued to arrive through 6:20)
Christopher Fleck (CF), Dewberry gave overview of CMSWS staff roles and introductions.
CF gave brief overview of project and project history.
CF explained changes in project layout design and project goals:
• Replace Riser, Outlet Pipe & Channel
• Install Emergency Pond Drain
• Water Quality Benefits (Detention, Controlled flow)
CF explained benefits of this system:
• Dam rehabilitation
• Emergency Pond Drain
• Water Quality
• Including CMSWS as Owner/Operator
• Reduced Costs
• Reduced Disturbed Area
• Reduced Construction Activity & Time for major Construction Tasks
• Smaller Pipe, Smaller Outlet Structure, Smaller Wall than previous design
• Shallower, Flatter Channel with utilization of stream restoration techniques (Step Pools)
CF/JS Explained Pond/Dam program overview and that there are 800+ ponds in the City of
Charlotte area.
Public Input - Questions & Answer
Residents asked if cost and time were the drivers for change.
• CF/JS Explained cost, regulatory requirements and previous commitments to the project
(ie: not draining the pond) were the driving factors in the design changes.
Residents expressed concern over easement acquisition based on previous design.
• AB indicated CMSWS/ Real Estate would review any concerns as requested.
Residents expressed concern over potential “whirl-pool’ flows where existing gabion spillway
meets proposed channel and possibility of erosion at that location causing potential damage to
property.
• CF/JS Addressed and explained concept of controlled flows from the design of the outlet
structure and how erosion is caused. Purpose of step pools and weirs to slow flow from
smaller storm events was explained.
• JS explained that existing erosion is currently occurring in the existing channel and
proposed design will control smaller storms much better than is currently occurring at the
site which should reduce the erosive flows.
• CF/JS/AB Explained that current models do not indicate increased potential for erosion in
excess of current condition for areas not proposed for improvement. Residents expressed
concern for existing channel condition.
• CF/AB indicated current design incorporated residents previous request to specifically
not add additional rip rap in the existing channel. However; additional rip rap can be
placed within easement (or outside easement with residents permission) beyond work
currently being proposed to address residents concerns based on revised plan.
• AB Explained that as a “project” the construction is covered by a 1 year warrantee and
that the City of Charlotte will be responsible for issues related to the project and
construction. As a project and easement grantor, any future stormwater requests are
treated as a “call back” with an “A” priority.
Residents asked questions about limits of Clearing and Tree Removal.
• CF Identified limits of disturbance of trees.
• GC/CF/JS Confirmed that trees on the dam embankment will have to be removed per
Dam Safety law. They explained that Dam Safety could order any trees on the dam or in
the riprap gabion spillway be removed if determined to represent a hazard to the dam.
Nor are not any new plantings permitted on the dam or in the emergency spillway.
• AB Explained that all trees to be removed during construction must be approved by City
Inspector prior to removal.
Residents asked about flows from proposed pipe, previous designs and also about the size of
the pipe and headwall and relative elevations.
• GC Presented history on previous design and changes in requirements affecting the
design.
• CF Explained that flows are significantly reduced from previous designs due to revised
regulatory constraints.
•
CF Explained that headwalls and channel are also smaller due to regulatory feedback
allowing more accurate modeling.
Residents asked about step pools.
• CF Explained that the step pools slow down and reduce the erosive potential of the water
leaving the pond.
• CF Explained that CMSWS expects existing base flow would keep a constant flow of
water through the channel.
• JS Explained that this base flow should prevent stagnant water and should not make
mosquito issue worse than it is. (Mosquito dunks available at local hardware store)
• CF/GC indicated base flow can’t be guaranteed especially in a drought situation but that
some flow has been observed since our involvement with the project.
Residents asked about trash around new outlet structure.
• CF Explained how the outlet structure functions and how the trash rack will function as
well.
Residents asked about schedule, construction and final closeout.
• GC/AB Gave brief overview of city process which allows at least 6 months for
construction.
• CF Gave brief overview of major construction activities and explained that the closeout
would be subject to getting vegetation to grow. The time of year and weather (drought
conditions) control vegetation growth and thus may affect final completion.
• AB Indicated contractors are not limited to working between the hours 7am-7pm and
could work 7 days a weeks if necessary. However; but that is not typical.
Residents asked about the aesthetics of outlet structure.
• JS Explained other designs considered
• AB/CF Explained how proposed structure would look & function
Misc Resident Items of note:
• Requested copies of design plans from CMSWS
• Requested that structures, pipe & channel be staked in the field
• Discussed existing trees planted by the City relating to previous design (dying). City to
coordinate replacement with Tom Martin.
• Concern over “call back time” for future issues. AB Explained that by granting an
easement the residents would be category “A”. This means the request is a high priority
for Storm Water and gets a quicker response time.
• Residents identified sink hole at drive between 10003 Swan Lake Ln and 100000 Swan
Lake Ln.
Meeting Ended at 8:10