20141233 Ver 1_Emails_20141218

Johnson, Alan
From:Johnson, Alan
Sent:Thursday, December 18, 2014 1:43 PM
To:Hinson, Isaac <[e-mail]> ([e-mail])
Subject:meadow ridge
Todays comments

1)The culvert is too wide. The upstream channel is only about 2 ft wide (base flow is even less), but the proposed

culvert is 6 ft wide. There should be a base flow and storm flow culvert (two culvert system) or:
Baffles can be used to create a “meander” through the culvert leaving a 2 ft opening and approximately 3 ft
gaps OR a single “curb” that runs the entire length with a 2 ft channel. The baffle system is used often by DOT.

2)Also to alleviate the proposed drop in culvert, it may be possible to slope the culvert, fill the scour hold and

bring the stream channel back closer to grade. As shown below. Either way with the propsed rip rap apron ,
there is a permanent impact to the channel.

3)At the grade of the channel at the upper end, place coir fiber matting (bio degrade) to catch sediment transport

rather than have a “graded” raw channel.

I believe that is all we talked about.

Thanks
Alan
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