HomeMy WebLinkAboutAGENDA REPORT 1994 0202 CC REG ITEM 08N i// � / � p'
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AGENDA REPORT
CITY OP MOORPARK
TO: The Honorable City Council
FROM: Kenneth C. Gilbert, Director of Public Works'7
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DATE: January 25, 1994 (Council Meeting 2-2-94) /r/
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SUBJECT: Consider Amendment to Contract with VCE, ACTION (.(1)4941,7,C:1
Inc. for the Design of the Arroyo Vista
Community Park Pedestrian Bridge
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OVERVIEW
This requests approval of an amendment to the subject Agreement to
allow for the preparation a hydrology report.
BACKGROUND
In April of 1993 the City Council retained the services of VCE,
Inc. to prepare the design for the Equestrian / Pedestrian Bridge
for Arroyo Vista Community Park. In August of that year the City
Council approved an amendment to that contract to expand the scope
of work to include the preparation of soils reports required for
the preparation of the design.
DISCUSSION
A. Floodplain Boundaries
The present channel and levies for the Arroyo Simi will not
contain storm flows from a 100-year storm. The Federal
Insurance Rate Maps (FIRM) for the City of Moorpark show an area
along the north and south sides of the Arroyo which are within
the boundaries of a 100-year storm and thus susceptible to
inundation.
B. Channel Widening Project
The Ventura County Flood Control District (VCFCD) is developing
a channel improvement project for a portion of the Arroyo Simi,
which includes the area where the Arroyo Vista Community Park
pedestrian / equestrian bridge is to be constructed. When that
project is completed a 100-year storm will be contained within
the channel .
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VCE Contract Amendment
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C. Bridge Design Parameters
The VCFCD channel improvement project calls for the lowering of
the water level at the planned location for the pedestrian
bridge. The design parameters for the pedestrian bridge are
based on the proposed channel widening improvement project, and
as such, calls for the construction of the bridge in a manner
which will be compatible with the future ultimate channel
widening project.
The proposed lowering of the water surface by the channel
improvement project enables the City to design and construct a
pedestrian bridge which is both shorter and lower than what
would be required if no channel modifications were being
planned. The resultant bridge project is more functional , more
compatible with surrounding properties and less expensive than
a longer and higher structure.
In light of the above, the pedestrian bridge design calls for
the elevation of the soffit (bottom) of the bridge to be lower
than the current elevation of a 100-year storm at the bridge
location. This factor, combined with the construction of a
slightly elevated bridge access roads and levy maintenance
roads, will have the effect of creating an obstruction to storm
waters flowing at and slightly lower than the 100-year flood
elevation at this location. Until the VCFCD channel improvement
project is completed, this obstruction could divert 100-year
storm flows in a manner which could inundate properties beyond
the present boundaries of a 100-year storm as presently shown on
the FIRM map.
D. Hydrology Report
VCE, the design consultant for this project, has given the City
a price of $5,000 to prepare a hydrology study to determine the
effect of the construction of the pedestrian bridge as presently
proposed on the flow characteristics of a 100-year storm at and
upstream of the project site.
E. Committee Review
At their January meeting, the Public Works, Facilities and Solid
Waste Committee (Councilmembers Wozniak and Montgomery)
discussed and concurred that this additional design work should
be performed.
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VCE Contract Amendment
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F. Fiscal Impact
1 . Fee Increase: A summary of the fee increase for these
additional services is as follows:
Existing Fee: $49 ,746
Increase for Soils Engineering: 3 ,968
Sub-total $53 , 714
Proposed Increase for Hydrology Report: 5,000
Revised Fee Amount: $58, 714
2 . Budget: The budget for this project for FY1993/94 is as
follows:
Spring / Tierra Rejada AOC (026) : $200,000
L. A. Avenue AOC (027) : 300 ,000
Project Total : $500 ,000
No additional appropriations are required to approve the
proposed increase in the design fee.
3 . Funding Sources: The above budget figures were "rounded-off"
from estimated amounts budgeted last year. These amounts do
not accurately reflect the approved funding ratio which is as
follows:
Spring / Tierra Rejada AOC (026) : 1/3
L. A. Avenue AOC (027) : 2/3
Actual costs will be distributed to these funds in accordance
with this ratio.
RECOMMENDATION
Staff and the Public Works, Facilities and Solid Waste Committee
recommend that the City Council take the following actions:
1 . Approve the additional services described above and an increase
in the contract fee from $53 ,714 to $58,714 ;
2 . Approve a ten per cent (10%) contingency and authorize the City
Manager to approve additional work, if required, not to exceed
ten percent of the revised contract amount; and
3 . Authorize the City Manager to sign necessary contract documents.
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