HomeMy WebLinkAboutSP201000044 Review Comments Special Use Permit 2011-08-25Megan Yaniglos
From: Victoria Fort [vfort @rivanna.org]
Sent: Wednesday, August 24, 2011 5:18 PM
To: Megan Yaniglos
Cc: 'Scott Collins'; Alex Morrison
Subject: The Granger - SUB2010 -119, SP201000044, SP201000045 - Comments
Attachments: The Granger.pdf
Follow Up Flag: Follow up
Flag Status: Flagged
Megan,
RWSA has reviewed the Granger Preliminary Subdivision Plat and Stream Crossings Plans as
prepared by Collins Engineering and dated 8/1/2011 and has the following comments:
Granger Preliminary Subdivision Plat:
Sheet 2 of 7:
1. The RWSA Interceptor downsizes to 18" at the manhole just south of Railroad Tracks. North of this
manhole, the Interceptor is 24 ". Please shift the arrow on the label to reflect this.
2. Label existing manholes as shown in the attached GIS map.
3. Based on field observations, the stream alignment south of the railroad culvert does not appear to match
that shown on the plans. Major erosion has occurred at this location, and it is believed that the introduction
of new culverts for the road crossings may cause similar alterations to the stream banks.
Sheet 3 of 7:
1. Show the location of the existing RWSA waterline.
Sheet 4 of 7:
1. Show the location of the existing RWSA sewerline.
Sheet 5 of 7:
1. Revise the waterline label at the bottom of the sheet to say "Existing 20" RWSA waterline ".
2. Revise the connection label at the bottom of the sheet to say "Connect to existing 20" RWSA waterline ".
3. Move the connection for the Granger Place sewerline so that it meets the 90- degree minimum allowable
angle between any incoming pipe and any outgoing pipe in RWSA manholes. This may require shifting the
new manhole and replacing additional sewer or connecting to the next downstream manhole.
4. Label existing manholes as shown in the attached GIS map.
5. The proposed sewer alignment does not appear to be feasible based on initial review.
Granger Stream Crossings Special Use Permits:
Sheet 2 of 2:
1. Please reverse the road profile for stream crossing #2 so that it matches the plan view.
2. Please show the locations of the existing sewerlines in the profiles for stream crossings 1 & 2.
Additionally, RWSA has the several concerns with the proposed sewer relocation. These may be
resolved in site plan review; however, please note that their resolution may affect the road alignments
and /or stream crossing locations as shown in the preliminary plat. RWSA will need to see a detailed
plan and profile for the relocated sewer before a design can be approved. I have provided a
summary of the major concerns below for the engineer:
1. The top of the pipe should be well below the bottom elevation of the stream bed at all stream crossings to
minimize effects on stream flows and the new sewerline.
2. New manholes must be a sufficient distance away from any stream banks or culvert outlets so that any
potential erosion will not compromise the manhole foundations or damage their exterior.
3. RWSA must be able to access the waterline for necessary maintenance, repairs, relocation, and
upgrades. The proposed alignment does not seem to be feasible due to the proximity of the sewerline to
the concrete culverts and the depth of proposed fill for the road.
As always, please do not hesitate to contact me with any questions or concerns.
Thanks a lot,
Vicki
Victoria Fort, EIT
Civil Engineer
Rivanna Water and Sewer Authority
695 Moores Creek Lane
Charlottesville, VA 22902
Phone: 434.977.2970 ext. 205
Fax: 434.295.1146