LTC 129-2007 Drainage Issues at Nautilus Westm MIAMIBEACH
OFFICE OF THE CITY MANAGER
200 LETTER TO COMMIS~I~
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TO: Mayor David Dermer and Members of the City Commission ~~-` ~
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FROM: Jorge M. Gonzalez, City Manager
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DATE: June 4, 2007
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SUBJECT: DRAINAGE ISSUES AT NAUTILUS WEST ~ v
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During the recent rain events, and especially two weekends ago, the City has experienced localized
flooding in some areas. These events were as a result of very intensive rains during short periods of
time which usually are the worst for drainage systems. This flooding was especially significant in the
area of 46th Street between Alton Road and Nautilus Drive.
The Nautilus West neighborhood where the subject area is located is a component of our Nautilus
ROW project which also includes Orchard Park. The area in question is within one of the priority
basins and will get significant improvements in the Nautilus project awarded to Ric-Man International
Inc., (Ric-Man) which is currently finalizing the design.
The BODR and the Design Criteria Package included increasing the size of the drainage piping from
Nautilus Drive to the East up to the waterway. The size would increase from the existing 21" pipes to
new proposed 36", 42"and 54"pipes. Replacement of existing structures and addition of new ones is
also in the proposed design. Additionally, three drainage wells will be placed in the area of 46th
Street and two drainage pump stations are located in Nautilus West. Finally, an additional proposed
outfall is also part of the design criteria.
The existing pipe between Alton Road and Nautilus Drive will not be increased because there is an
interrelationship with drainage in Alton Road which involved permitting from the Florida Department of
Transportation (FDOT) and they did not think that this enhancement was needed at the time they did
their Alton Road improvements. Therefore, the City left the system in this block out of the ROW
project improvements although the existing 21"pipe within the block could be connected to the new
system in the future if it were warranted. We believe, though, that with the increased size new piping,
the new structures, the new wells and pump stations, and the potential additional outfall, the overall
drainage system in Nautilus West will be greatly enhanced and would resolve, inmost instances, the
conditions experienced during the recent event.
We will review the design and the calculations forthcoming from Ric-Man and if any additional
adjustments are needed we will make them before the construction in the area begins. At this time,
though, we do not contemplate construction starting in the Nautilus West area until late this year or
early next year. The construction on the project is beginning with water pipe improvements in Orchard
Park while Ric-Man completes the drainage design. This will help accelerate the overall
schedule. Residents affected by the event have been given this information and some have and will
continue to visit the CIP Office to discuss the design and look at the documents with our staff.
If you have any further questions lease do not hesitate to contact me.
C: Tim Hemstreet, Assistant City na r
Jorge E. Chartrand, CIP Dire o
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