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TO: Mayor Richard C. Irvin
FROM: Tim Weidner, P.E., Professional Engineer
DATE: March 18, 2019
SUBJECT:
Resolution to approve a professional services agreement with Crawford, Murphy & Tilly, Inc. in the amount of $229,800.00 for the 2019 Water Main Flushing Program.
PURPOSE:
To continue providing high quality water to the City's water customers.
BACKGROUND:
Regular maintenance of the water distribution system is necessary to keep the system working well. One standard maintenance activity is a system-wide water main flushing program.
Because water mains are sized to handle fire-fighting flows, which may be several times larger than domestic and commercial water use needs, the velocity of flow through water mains is normally fairly low. Low velocity flow allows solids to settle on the bottom of pipes. These deposits can be a source of color, taste, or odor when they are stirred up by short-term increases in flow, such as water main breaks or hydrant flow testing by the Fire Department. Implementing a City-wide, planned and organized flushing program allows the deposits that settle in the bottom of a pipe to be removed from the water distribution network systematically.
Crawford, Murphy & Tilly, Inc. (CMT) developed a computer model of the City's Water Production Plant and water distribution system in the 1990's. They have updated the model periodically, including a recent update that began in 2017. CMT uses the model to determine which valves need to be closed in sequence to produce flow velocities high enough to flush deposits from the water distribution network. The City began planning its system-wide water main flushing program in 2012. Flushing began with Area 1 in 2013. By 2016 the first system-wide flushing program had been completed. The 2019 Water Main Flushing Program will be the third year of the second cycle through the program.
As part of the program, staff operates valves and hydrants, tests water quality, adjusts the computer model, posts informational signage, and works around the schedules of critical water users. In past years this work has been provided by CMT staff. This year City work forces will assume a majority of the field labor required to implement the project. CMT will still provide the computer modeling, assistance with the work items at the beginning of the project, and lead City staff in the field when flushing begins. Once the program has been established, the City may continue the flushing program without assistance from CMT. This would be contingent upon City staff members being able to work independently and have enough available staff to complete the program.
DISCUSSION:
Exhibit A in the attached professional services agreement identifies the areas planned for water main flushing in 2019 as three sub-areas of Area 3 (Zone 3A, 3B, and 3E - shown in yellow), Area 4 (shown in purple) and one sub-area of Area 5 (Zone 5A - shown in light orange). Exhibit B shows those areas on a map. Exhibit C shows the billing rates which are going up by 2.9% over 2018 rates.
The local preference policy does not apply since it is a professional service not required to be bid.
Account 510-4063-511.38-68 has $372,000 budgeted in 2019 for these services.
IMPACT STATEMENT:
Customers may experience fluctuating water pressure and some water discoloration while their water main is being flushed. If these disruptions occur, they will typically be limited to a few hours during the work day. Customers in and near the project area will be notified in advance of the flushing program using multiple forms of communication. Informational flyers will be mailed in April, before the start of the program. Signs will be placed along prominent streets a few days before flushing begins in each neighborhood. Both the flyer and the signs will direct customers to call a hotline with a recorded message updated at the end of each work day. The message describes the locations where water mains will be flushed the next day in both English and Spanish.
Traffic may be affected by short-term lane closures near open fire hydrants.
RECOMMENDATIONS:
Staff recommends the proposed resolution be adopted.
cc: Alderman Garza, Chairman
Alderman Donnell
Alderman Bohman
Alderman Hart-Burns, Alternate
CITY OF AURORA, ILLINOIS
RESOLUTION NO. _________
DATE OF PASSAGE ________________
title
A Resolution approving a professional services agreement with Crawford, Murphy & Tilly, Inc. in the amount of $229,800.00 for the 2019 Water Main Flushing Program.
body
WHEREAS, the City of Aurora has a population of more than 25,000 persons and is, therefore, a home rule unit under subsection (a) of Section 6 of Article VII of the Illinois Constitution of 1970; and
WHEREAS, subject to said Section, a home rule unit may exercise any power and perform any function pertaining to its government and affairs for the protection of the public health, safety, morals, and welfare; and
WHEREAS, regular maintenance of the water distribution network is necessary to continue providing high quality water to the City's water customers; and
WHEREAS, a water main flushing program is part of the City's maintenance of its water distribution network; and
WHEREAS, account 510-4063-511.38-68 has $372,000 budgeted in 2019 for this project.
NOW, THEREFORE, BE IT RESOLVED by the City Council of the City of Aurora, Illinois, as follows: a professional services agreement with Crawford, Murphy & Tilly, Inc. in the amount of $229,800.00 for the 2019 Water Main Flushing Program is hereby approved, and the Director of Purchasing is hereby authorized to enter into such a contract on behalf of the City.