HomeMy WebLinkAboutA034 - Letter from Fox Engineering dated August 9, 2004 - storm water detention pond engineering August9, 2004
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Tracy Warner
4' AUG f 0 2004
Municipal Engineer
City of Ames - -
515 Clark Avenue
Ames, Iowa 50010
RE: The Reserve Subdivision, Ames, Iowa
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Fox Ref. No. 5180-98a.600
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d
> Dear Tracy:
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This letter is in response to the City of Ames demand that a storm water
y detention pond be installed in the Reserve Subdivision at the location of the
previous sediment control pond. As we have indicated, a detention pond was
not required by the City nor was a pond proposed as part of the development.
The Reserve's storm water quality and storm water detention requirements
e were to be fulfilled by the City's construction of the ponds on the former
o Stonebrooke property as part of the Hallets watershed protection. As evidence
we offer the following:
a1. The storm water management report does not reference a detention
pond or size nor would calculations submitted to size such a pond
r (because the City was fulfilling this requirement with their purchase and
3 construction of the Stonebrooke ponds). The report specifically
mentions the storm sewer running through the area and the method of
w its outlet (which would preclude the use of detention pond). As an
U) aside, the amount of"uncontrolled" drainage is very small as referenced
in the report.
N
3 2. The erosion control plan and report does not reference any detention
M facility — only the temporary sediment control pond. The sediment pond
was set up as a temporary feature with temporary piping and inlet. The
U) sediment pond as built was in excess of the requirements shown the
construction plans. An additional 4-6 feet was added to the sediment
pond height, which provided control in excess of the requirements.
3
r 3. The preliminary plat does not reference a detention pond nor are
impoundment easements provided.
4. The construction plans reference only the sediment control pond and do
w not reference a permanent detention pond. Piping and materials used
for the construction of the pond are not the same materials that would
have been used for a permanent structure.
1601 Golden Aspen Dr. 5. No impoundment easement was shown on the final plat. The only
Suite 103 easement shown are the drainage easements, which are insufficient in
Ames, Iowa 50010 width to construct any pond, as they were intended for pipe and channel
1.515.233.0000 flow. The rear (west) drainage easement contains most of the area of
1.800.433.3469 the existing channel at the rear of the lots.
Fax 1.515.233.0103
www.foxeng.com
info@foxeng.com
6. The lot density calculations submitted to the City Planning & Housing
Department subtract the various easements and conservation areas
from the area used to calculate density. There was no detention pond
included in the area.
7. The size of the lots next to the drainage easement preclude taking up
any area for a detention pond. The lots are relatively small and a pond
would be a major impediment to lot sales. Lots 36-41 were unsaleable
due to the sediment pond because the impoundment was well into the
buildable portion of the lots. A detention pond would have caused a
similar effect and made the lots unsaleable.
This project was thoroughly scrutinized by the City at every step due to the
controversy surrounding the issue of development of the Hallets quarry area.
This issue (of detention) was not missed; it was assigned to the City as part of
their larger project and cooperative effort between the City and the Developer.
Sincerely,
l
Sco t Re a , P.E.
Cc: Ted Tedesco, Mayor
Steve Schainker, City Manager
Rick Tollakson, Hubbell Realty
Bill Spencer, Regency Homes
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