HomeMy WebLinkAboutSDP2006-00032 - OHWM~AR~'HRISS /7,
ENGINEERING
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Mr. Greg Ballard
Associate Planner
Jefferson County Dept. of Community Development
621 Sheridan St.
Port Townsend, WA., 98368
Re: Tom Hamilton Beach Access Stairs
41 Madrona Beach Dr.
Port Townsend, WA 98368
Subject: Jefferson County Flood Damage Prevention Ordinance
Deaz Greg,
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SDP oc~-ood32
P.O. Box 5537
Rremertori, WA 98312
P: 360 - 792.- 2421
F: 360 - 792 - 2949
harry.williams@marchriss.com
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SEP 21 200
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Per our telephone discussion, and after reviewing the Jefferson Flood Map you
sent me, the established flood surge elevation had not been established for the location of
Mr. Hamilton's stair. However, you had mentioned that a 3' high surge above the high
water line would be a safe assumption. The platform is approximately 7' above the high
water line, therefore, the platform would still be about 4' above the surge elevation. This
means that the 8x8 posts would be partially submerged.
After reviewing the stair design, including foundation and framing connections, I
have concluded that the stair platform can safely resist the potential hydrodynamic forces
from potential flooding.
In addition, based on DOE's requirement for reducing the platform size from
7'x10' to 4'x4', I have revised the calculation package that was originally submitted to
reflect those changes. It is my understanding that Mr. Hamilton will resubmit the revised
calculations.
Please call me if you have any questions.
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Sincerely, ~~I ~'v ~ -
Harry Williams P.E. r0 ~ae'° 5~
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