HomeMy WebLinkAboutBritton Review Comments 2020-12-02 T. G . MILLER , P. C .
E N G I N E E R S A N D S U R V E Y O R S
605 West State St.Suite A I Ithaca,NY 14850 1 phone 607-272-6477 1 fax 607-273-6322 1 www.tgmillerpc.com
December 2, 2020
C.J. Randall,Town Planning Consultant
Town of Lansing
29 Auburn Road
Lansing, NY 14882
Re: Britton Cluster Development,Storm Water Pollution Prevention Plan Review
Dear C.J.,
We received a Storm Water Pollution Prevention Plan (SWPPP) and drawings ST-1 to ST-11
dated August 5, 2020 prepared by Timothy C. Buhl, PE.and have summarized our comments
below.
Stormwater Management
1. Provide singed Owner and SWPPP preparer certification forms.
2. Move the pond outlet control structure and spillway to pond 1 (north)
now that N. Triphammer ditch is said to be flowing north.
3. Provide topographic survey with one-foot contours at the proposed road
entrance and area of the proposed ponds to ensure proposed grades,
ditch/pipe inverts and pipe cover can be achieved. Current grading shows
N. Triphammer ditch flowing south.
4. Coordinate with Town highway superintendent for adequate access to
maintain ponds. Consider increasing the width of the berms from 4'-6' to
8'-10' min.
5. Delete or revise note on sheet ST-9 for emergency overflow elevation
911.00
6. Pond appears to be spilling over the emergency spill 965.75 in the 100-yr
storm but Hydrocad does not have the emergency overflow modeled.
Revise model accordingly and verify flows rates are reduced for the
100-yr storm.
7. Show approximate limits of disturbance line on sheet ST-1 and revise
"Total Disturbed Area" note on ST-1 and SWPPP to match. Provide
waiver request if disturbance will be great than 5 acres at any one time or
provide a note on the plan if disturbance is not to exceed 5 acres at any
one time.
8. Continue to coordinate with Tompkins County Highway Department for
drainage and entrance improvements within N. Triphammer Road ROW.
Provide a copy of all permits required for the project.
David A.Herrick,P.E. Dondi M.Harner,P.E., Lee Dresser,L.S.
Frank L Santelli,P.E. LEED A.P. Darrin A.Brock,L.S.
Andrew J.Sciarabba,P.E.
9. Include note on the plans requiring a pond volume certification to be
completed prior to dedication to verify as-designed volumes and
elevations are achieved.
Road Design
1. Provide road signage and striping plan and sign detail with breakaway base.
2. Update Typical Roadway Cross Section detail on sheet ST-2 to conform with
Town's latest detail for asphalt concrete pavement surface. Oil and stone surface
treatment is not permitted.
Water System
1. Provide Engineer's Report for municipal watermain extension to accompany
DOH Form 348.
2. Provide boring detail with steel casing pipe,casing spacers, rubber end seals,
etc.Label boring and receiving pits on the plan with dimensions.Add note to the
plans that existing main is to be exposed prior to the boring to verify existing
watermain elevations.
3. Revise watermain location and notes on sheet ST-5 to be consistent with
proposed conditions.
4. Provide watermain sampling tap locations,sequencing,disinfection and testing
notes.
5. Provide cut-in tee with three-way valve at the connection to the existing public
watermain.
6. Provide topographic survey with one-foot contours at the proposed water main
across N.Triphammer Road.Show all existing utilities including overhead and
underground.Consider locating nearest fire hydrant and water vales.
Drainage District Report
1. Report to be finalized after final plat approval.
2. Include reference to all tax parcel numbers once issued and include
estimated district fee for each parcel.
3. Remove reference to individual lot stormwater practices from the drainage
district. These practices are to be maintain by the land owner per separate
agreement.
4. Revise district map to clearly show easements, permanent practices to be
maintained, district boundary and tax parcel numbers.
Final Plat
1. Adjust lots lines on all plans to match the final plat.
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2. Clarify overlapping drainage easements.
l label drainage
--
�easement
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RESERVED AREA FOR
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- Are these
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If you have any questions please feel free to contact me or we can arrange a time to meet to
review in more detail.
Sincerely,
0 -
Donald Harner, P.E.
Enclosure: Highway Specifications
Cc: G. Caward,Jr., Chair
E. LaVigne, Supervisor
L. Day, Code Enforcement
C. Purcell, Highway Superintendent
G. Krogh, Esq.
D. Herrick,Town Engineer
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