HomeMy WebLinkAboutWPO201800014 Plan - VSMP 2020-01-24SHARP ENGINEERING, P.C.
Design Focused Engineering
December 02, 2019
Emily Cox
County of Albemarle
401 McIntire Road, North Wing
Charlottesville, Virginia 22902
APPROVED
by the Albemarle County
Community Development Department
Date 1 /24/2020
File WPO201800014
RE: WP0201800014 Hansen Road Church — VSW Amendment
Dear Emily,
Included in this submittal is a request to remove one of the proposed storm structures, AB I, for the
approved Hansen Road Church plan. The survey we received when designing the stormwater
infrastructure for this site had not included the existing pipe that extends from a structure in Abbey Road
to the existing structure along Hansen that we are now proposing to leave in place and cover. In the
approved plan, we proposed structure AB with a new 48 LF pipe extending to it from the existing
manhole located in the middle of the proposed entrance. Once work began onsite we realized there was
already a pipe in place where we were proposing one, and the angle of the pipe would not work with the
proposed structure. After revisiting the drainage calculations, it appears that water from the original AB
drainage area would have above 90% capture and an acceptable width of spread at the next inlet Al, and
would eventually be 100% captured at X4 further down Hansen Road. These calculations and a diagram
are included, as well as the original drainage area sheet from the approved plans. Drainage areas have not
changed, AB and Al are just combined.
If you have any questions or concerns about these revisions, please feel free to contact me at
kendra(iDshimp-engineering.com or by phone at 434-227-5140.
Regards,
4J1G-'
Kendra atrick
Shimp Engineering. P.C.
912 E High St Charlottesville, VA 22902 1434.227.5140 1 shimp-engineering com
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Hansen Road Church
30 0 30 60 90 Structure AB 1 -X4 Revisions
GRAPHIC SCALE: 1 "=30' Last Revised: 10-24-2019