20060447 Ver 2_Staff Comments_20090804

06-0447 Olde Towne
AML comments
August 4, 2009
Please provide a clear, current summary of the current status of the stormwater
management plan for each phase of this project.
2. For each phase that is currently approved by the City of Raleigh, please provide
documentation of the City's approval of the stormwater management plan for this
project by providing EITHER:
• A valid approval letter from the City of Raleigh indicating that the proposed
activity has an approved SMP and one copy of the approved SMP, including
plan details, calculations and other supporting information, OR
A set of stormwater plan details and calculations stamped as "Approved" by
the City of Raleigh.
3. Any phases of the project that are proposed to be treated by a wet detention pond
must meet the requirements of the Neuse Buffer Rule. Per the requirements of the
Neuse Riparian Buffer Rule, all stormwater drainage that is not being treated by a
BMP that removes 85% of TSS and 30% of TN must be discharged through a
correctly designed level spreader. Level spreader design requirements are set
forth in Chapter 8 of the North Carolina Stormwater BMP Manual, available at:
littp://h2o.enr.state.nc.us/su/bmp forms.htm. Please provide one Level Spreader
Supplement Form for each proposed level spreader, available at the same web
address. Please include the Required Items checklist and all items listed therein.
4. For any phases of the project that do not yet have approved stormwater
management plans from the City of Raleigh, please provide a conceptual
stormwater management plan for the project that includes the following:
a. A depiction of the drainage areas in the future phases.
b. An estimation of the percentage imperviousness associated with each of
the drainage areas.
c. A calculation of the water quality volume associated with each drainage
area.
d. A depiction of a proposed BMP (state the type of BMP you plan to use) on
the site plan that is correctly sized based on the water quality volume.