Lake Lucy Rd and Powers Blvd Watermain Extensions Project
Watermain loops are essential to any robust and healthy water system network. Looping improves reliability by feeding water from two directions rather than one, which subsequently allows service to continue during an event that may otherwise cause disruption to water service, such as a watermain break or scheduled maintenance. Looping can also reduce water quality problems by allowing circulation even at times of low flow which prevents mineral precipitants from collecting at low points in the pipeline. Additionally, looped systems also permit greater water flow to an area when there is a fire or other source of high demand.
Two critical areas in need of either a watermain loop or reinstituting a failed watermain loop were identified by staff in the Lake Lucy Road and Powers Boulevard Watermain Extensions Project No. 20-04.
Lake Lucy Road Watermain Extension (Base Bid)
Within the city's high pressure zone there is a large service area located between Galpin Boulevard and Powers Boulevard, north of Lake Lucy Road, that is fed by a single feed point and is not currently looped (see image below). Watermain within the single feed point area has experienced multiple breaks which has escalated the need for a secondary feed point to loop the system to alleviate possible issues. While the system could be back fed with the low pressure zone in an emergency situation and during watermain repairs, it creates adverse pressure scenarios for users in these areas, and in a worse case scenario adverse fire flow conditions.
Due to the critical need to loop the high pressure zone in this area, staff designed a watermain alignment that utilizes existing unimproved public right-of-way. The new alignment will create the much needed looped water system in the area which will ensure better serviceability, reliability, and water quality to users.
Powers Boulevard Watermain Extension (Bid Alt)
An existing 8" CIP watermain installed in 1971 and abutting Powers Boulevard has experienced a series of breaks. The breaks occurred within the area of a retaining wall that supports a public trail on the east side of Powers Boulevard. As this retaining wall has geogrid reinforcement located above the watermain, staff determined that the watermain coupled with its location makes it essentially unmaintainable and the watermain should be relocated. In the fall of 2018 the city's utility department installed a plug north of the retaining wall and closed the valve to the south in order to isolate the failing section of watermain (see image below). This has eliminated the loop for this section of the city's water system while it is temporarily being back fed further to the north.
Working with Carver County, staff designed a new watermain alignment on the west side of Powers Boulevard ensuring minimum impact to the County's right-of-way. The new alignment will also facilitate long-term maintenance along with reinstituting the looped water system in the area which will ensure better serviceability and water quality to users.
Both project areas will be built in accordance with the city's 2020 Standard Specifications and Detail Plates and will secure all appropriate permits from regulatory agencies including Carver County and the Minnesota Department of Health. Construction plans and specifications are attached for reference while both are undergoing quality assurance and quality control reviews.
Widmer Construction, LLC is the apparent low bidder. A resolution to accept the bid and award the contract is scheduled to go before council on September 28, 2020. If the resolution is approved, construction could start as early as the first week of October.
The proposed remaining project schedule is as follows:
|Lake Lucy Road and Powers Boulevard Watermain Extensions Project|
|Advertise for Bids||August 27, 2020|
|Bid Opening||September 17, 2020|
|City Council Meeting -Accept Bid & Award Contract||September 28, 2020|
|Start Construction||October 5, 2020|
|Substantial Completion||November 6, 2020|
|Final Completion||Summer 2021|
|Project Notifications Disclaimer|
|Due to the variability of construction, updates typically do not include specific details such as day-to-day scheduled activity. The City's inspector or contractor will notify occupants directly if they will be impacted by a utility service shut down (example: water shutoff), or work (such as excavation or new curb) that will impede access to the property for a period of hours or days.|