THE CORPORATION OF THE
CITY OF PORT COQUITLAM

B.R. Kirk, March 1, 1989
City Administrator

T.M. Chong, P, Eng. td
City Engineer

SUBJECT: Coquitlam River Dyking Project - Internal Drainage Study
(Public Works Committee Meeting February 28, 1989)

Recommendations:

1, That Associated Engineering (BC) Ltd. be retained to undertake the
Coquitlam Dyking Project Internal Drainage Study in accordance with the
proposal submitted by them dated February 20, 1989.

2. That the upset fee of $12,400 for this study be funded from the 1989
Unallocated Public Works Capital Budget.

Background and Comments:

Due to the recent meetings on the Coquitlam River Dyking Project City
Council is well acquainted with the status of this project. Now that the
conceptual designs are close to being finalized the time has come for the City
to consider the internal drainage aspects of the low lands behind the proposed
dykes. Under the terms of the Fraser River Flood Control Program this is
clearly the responsibility of the municipality. Notwithstanding this,
attempts by staff have been made to persuade the Project Manager to include
this work within the scope of the Dyking Project at the senior governments’
cost. The responses have been firmly negative.

It is important to undertake the internal drainage study in that while the
construction of dykes along the Coquitlam River will offer protection from
flooding of the adjacent properties due to heavy run-off in the river, these
dykes will do nothing to prevent the flooding of low-lands due to the surface
run-off from the internal drainage system. Whenever the water levels in the
river exceeds those of the outfalls draining the internal run-off the
respective flap gates will close thereby preventing further drainage of any
internal run-off. Dependent upon the characteristics of the internal drainage
system and the rainfall, provisions such as pumping may have to be constructed
in order to prevent the flooding of the land side of the dykes. The proposed
internal drainage study will provide us with the needed information.

One of the main reasons that Associated Engineering (BC) Ltd. is
recommended to undertake this study is because they have all of the relevant
information pertaining to the backwater curves along the river and other
aspects of this project. To bring another consultant in to do this study
would likely cost more due to the added cost of project familiarization.
There are also other possible problems with two separate consultants each
doing a portion of the project and not integrating their work to arrive at a
better end product.

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