HomeMy WebLinkAboutEngineering Review #1GetGo 146th & Gray – Engineering and SWPPP
American Structurepoint, Inc.
July 15, 2015
Page 1 of 3
July 15, 2015 1st Review
Mr. Bradley Schrage, P.E.
American Structurepoint, Inc.
7260 Shadeland Station
Indianapolis, IN 46256
RE: GetGo 146th & Gray
Docket No.
Dear Mr. Schrage:
The review of the proposed construction plans and drainage calculations for the above referenced project,
dated May 20, 2015, has been completed. The submittal is in need of additional information in order to be in
compliance with the City of Carmel Engineering Standards. Please revise the plans in accordance with the
comments below.
SWPPP:
1. Please provide an Operation and Maintenance manual for all post-construction stormwater quality
measures.
2. Please provide an update on the wetlands study. Wetlands shall be delineated on the construction
plans. Please provide the approved mitigation plan for the wetland areas on this site.
3. Please provide the Stormwater Pollution Prevention Plan in the required City of Carmel format. See
attached.
4. Please include with the soils map a brief description of how the site has accommodated the existing
soil limitations.
5. Please provide a Demolition/Initial Storm Water Control Plan erosion control plan for the demolition
and clearing of this site. This plan shall include the location, dimensions, specifications, details and
the monitoring and maintenance guidelines for demolition and clearing. Storm water controls needed
for demolition are shown include Construction entrance/staging area/ NOI posting, existing inlet and
culvert protection, perimeter protection, tree protection, and temporary stabilization. The demolition
and clearing shall be included in the sequencing of work on the SWPPP.
6. Please indicate the location of proposed soil stockpiles, borrow, and/or disposal areas, listed and
shown on plans. If not anticipated, one must still be shown.
7. Please provide an e-mail address for the trained individual responsible for stormwater pollution
prevention for the project site.
8. Please revise the “SEEDING” note in the legend on Plan Sheet C501 to read “SEEDING AND
MULCH”.
9. Please revise the “EROSION CONTROL BLANKET” note in the legend on Plan Sheet C501 to
include “SEEDING”.
10. Please include native seeding on the sloped areas of the detention area.
11. All BMP’s are to be contained in exclusive or complimentary easements, with an adequate width
beyond the actual footprint of each BMP, as well as a 20-foot wide access easement from a public
right-of-way to each BMP and detention facility. A stabilized access is to be provided for any
structural BMPs 15’ or further from the right-of-way. Please revise accordingly.
GetGo 146th & Gray – Engineering and SWPPP
American Structurepoint, Inc.
July 15, 2015
Page 2 of 3
12. Please indicate in the plan view on plan sheet C501 the locations of the “DO NOT MOW OR
SPRAY” signs proposed, as well as a detail in the legend denoting the sign locations. Please revise
accordingly.
13. Please label all BMP’s and the diversion structure in the plans.
14. Water quality treatment shall include an Aqua filter with the Aqua Swirl unit. Please revise
accordingly.
15. A pond liner will be required for the wet pond to the normal pool elevation, and the construction plans
shall include liner details and specifications. Please revise accordingly.
16. No runoff from under the dispenser canopy will be routed through the wet pond. A dead end sump
designed to capture and potential spills that may occur. The operation and maintenance should be
addressed in the Operation and Maintenance manual. Please revise accordingly.
17. An emergency storm shut off valve shall be installed on the storm system. Please revise accordingly.
18. Additional erosion control measures within the creek immediately downstream of proposed Storm
Structure 201 and the embankment to be constructed for the entrance off of Gray Rd. is recommended.
Temporary measures should be provided in addition to silt fence for the embankment until vegetation
is established. Please review and revise.
Engineering:
1. Please label the radii of the parking islands.
2. The maximum food elevations need to be noted on the plans so one may reference the differing MFPG
and MLAG on the plan sets.
3. Please include additional spot elevations on the sidewalk from 146th St to the north side of the parking
lot, as well as the sidewalk from Gray Rd. to the west side of the parking lot, to differentiate between
sloped areas and landing areas.
4. Please review the ADA ramps proposed. Plan Sheet C201 specifically calls out a Type “D” ramp, but
no details are provided in the plans. Plan Sheet C600 includes The City of Carmel Standard Drawing
10-43E (Type “K” ramp), but there are no Type “K” ramps called out on the plans. On Plan Sheet
C300, it appears Type “G” ramps are proposed at the entrances, but there are no keynotes or details
provided. For all proposed ADA ramps located in existing or proposed right-of-way, INDOT standard
ADA ramp details shall be provided.
5. Please include the MFPG and MLAG elevations for the proposed building and definitions of each are
provided. Please confirm the basis for establishing the MFPG and MLAG elevations, assumed to be
1-foot above the maximum water surface elevation resulting from the 100-year storm event on-site
with all inlets plugged.
6. Please dimension taper lengths and widths for auxiliary lanes.
7. An acceleration taper will be required for the Gray Road entrance, and adequate left turn movement
from southbound Gray Road will need to be provided.
8. The existing 15-inch concrete pipe that appears to convey runoff from Gray Road should be
intercepted north of the proposed entrance and routed through the detention pond via proposed Storm
Structure #6. Note that all storm sewers that convey off-site water (from the right-of-way or other
properties) shall be contained in a 30-foot easement.
9. A manhole will be required for the connection of Storm Structure 201 to the existing 35 inch steel
culvert crossing under Gray Rd. Please revise the Structure Data Table to include the top casting
elevation, upstream pipe elevation, downstream pipe elevation, pipe length, pipe material, pipe size,
type of structure and detail reference to type of structure and any notes related to the structure.
GetGo 146th & Gray – Engineering and SWPPP
American Structurepoint, Inc.
July 15, 2015
Page 3 of 3
10. Detention facilities designed with permanent pools or containing permanent lakes shall have a water
area of at least one-half (0.5) acre with a minimum depth of eight (8) feet. The pond area shall have
no extensive shallow areas, except as required to install the safety ramp, safety ledge, and stormwater
BMPs. Please review and revise the proposed detention area.
11. An emergency spillway shall be provided to convey, without overtopping the detention facility banks,
one and one-quarter (1.25) times the peak inflow discharge and peak flow velocity resulting from the
100-year design storm event runoff from the entire contributing watershed draining to the
detention/retention facility, assuming post-development condition on-site and existing condition off-
site. The proposed spillway will be reinforced, the location of which will be shown on the plans, to
include details and specifications. Calculations shall be provided to ensure the capacity meets the
above requirements.
12. It is recommended to rotate the outlet control structure to the east to provide a more direct outlet to the
Mitchener Ditch.
13. Please include the following note on the plans: “Damage to the existing right-of-way shall be
restored/repaired to the satisfaction of the City at the completion of the project. The Contractor is
encouraged to inspect the right-of-way with the City prior to the start of construction to document the
existing condition of the right-of-way.”
Please include with your submittal, one (1) copy of the comments indicating the action taken or a written
explanation for action not taken. Construction plans and drainage calculations are not to be re-submitted
without implementing changes with respect to any and all review comments from the City of Carmel and the
Hamilton County Surveyor’s Office.
Please contact me at (317) 780-1555 ext. 112 with any questions.
Sincerely,
CrossRoad Engineers, P.C.
Gregory J. Ilko, P.E.
Sr. Project Manager
copy: Jeremy Kashman, City of Carmel Engineer
Greg Hoyes, Hamilton County Surveyors Office
John Thomas, City of Carmel MS-4 Operator
Alex Jordan, City of Carmel Engineering Department
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