20040124 Ver 5_Email_20080102

Re: R-2813B Response to NCDWQ's Questions
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Subject: Re: R-2813B Response to NCDWQ's Questions ~ ~J~
From: Michael Turchy <[e-mail]> ~~
Date: Wed, 17 Oct 2007 14:00:17 -0400
To: [e-mail]
Hey Brian,
I have forwarded your questions from this morning to all of the relevant engineers for their approval/
comments. Below are their replies: .
1. Sheet 5 Structure 38, can we angle the pipe into the energy dissipater?
We will move the system nutlet to tie inter the energy dissipater.
2. Sheet 6 B Structure EX8, is energy dissipation needed?
Na, Na increase in discharge is anticipated.
3. Sheet 6 B Structure emptying 124/ 136 is energy dissipation needed?
Na. Na increase in discharge is anticipated. Also (and this applies to
question 2 as well} there are very steep slopes and na propased wark an the
nutlet of these structures.
4. Sheet 9 Structure EX 4, is energy dissipation needed?
Na. Na increase in discharge is anticipated.
5. Can 3:1 slopes be used instead of 2:1 slopes if acting as grass swale/ storm
water treatment situations.
There are na areas where we cauld use grass swales as starm water
treatment due to tapagraphy.
6. "Can wedge shaped footers to prevent material from piling up in front of
bents?" Is this possible? what type of bents were proposed?
In response to the Bent question, we offer the following:
Tlae F3et7ts are a standard NC~DOT Post aa~d Beam Bent sulaported otx Drilled Piers. There tivill be 4
~wund coltunns a~-e 4'-6" lacatcd in tl~e t•iver. Tl1e cvl~rna~r~s are spaced at 34'-0" in the clirectivn of
the river f1v~v. This l<~rger spacing {than standard ~C1)O'I~ designs} will decrease tl~e potential for
build-up vfi debris ~~tllowing tl~e del7ris tv tlo~~° around and between tl~e cvltnn~ns. In addition, this
detail has not al~~-a.ys proven tv be effective in deterring debris build.-u:l~. I~'vr these reasons, we
would cwt recommend providing a ~~~edge shaped ctitensivn to the bents in the river.
Please let me know if I have misunderstood any questions or you would like more information.
Thanks,
Michael
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