20151031 Ver 2_Gateway Marketplace stormwater_20160907

Strickland, Bev
From:
Kim Williams <[e-mail]>
Sent:
Wednesday, September 07, 2016 11:14 AM
To:
Shaver, Brad E SAW; Steenhuis, Joanne
Cc:
Jeff Soble; Andrew Moriarty; Cord Blendermann
Subject:
Gateway Marketplace stormwater
Hi Brad and Joanne
Brad- I know you are out in the field today and tomorrow, but wanted to get feedback from Joanne and you about
stormwater at Gateway Marketplace when you have a moment.
Andrew Moriarty with Bohler Engineering was able to speak with Pat Donovan Potts yesterday. She told him that the
City will not allow untreated runoff directly into wetlands. They will allow the use of the permeable pavement in
combination with an underdrain system that will collect the stormwater that infiltrates through the permeable
pavement that discharges to a grass Swale upstream of the wetlands and then discharges into the wetland. She said
that no one has done this in the past, but it is something that she would entertain.
We have a few questions/thoughts regarding this:
1. The engineer is anticipating there may need to be 5' to 10' of additional fill in the NW corner of the site for the
grassed Swale, which will likely result in additional wetland impacts. Is this acceptable to you in order to direct
treated stormwater to the wetlands?
This concept is preliminary in nature right now. We don't yet know the costs associated with constructing this
system or if the City will ultimately permit it (Pat said they would consider it). So we are concerned that if
anything too specific is required in the Section 404/401 permits, we may find down the road that it is not
feasible or needs to be modified for one reason or another. How do we condition the permits to allow some
flexibility in design?
Let me know your thoughts.
Thanks!
Kim
Kim Williams I Environmental Scientist
Land Management Group, Inc I Environmental Consultants
Direct: 452-0001 x 1908 1 Cell: 910.471.5035 1 Fax: [phone]
3805 Wrightsville Ave., Suite 15 1 Wilmington, NC 28403
Email: [e-mail] I Website: www.lmgroup.net