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File #: 25-2038    Version: 2 Name: 12/15/25 Resolution to Approve a Construction Contract with Sorensen Gross Company LLC
Type: Resolution Status: Passed
File created: 12/15/2025 In control: City Council
On agenda: 12/15/2025 Final action: 12/15/2025
Enactment date: 12/15/2025 Enactment #: R-25-441
Title: Resolution to Approve a Construction Contract with Sorensen Gross Company LLC in the Amount of $482,205.00 for the Water Treatment Services Unit Flocculation 4/5 Gallery Improvements Project (RFP 25-48)
Attachments: 1. PublicImprovement_RFP 25-48_Contract.pdf, 2. RFP_25-48_Addendum1_2025_1029.pdf, 3. rfp_25-48_proposaltab.pdf, 4. Sorensen Gross_Proposal For RFP# 25-48 Ann Arbor WTP Floc 4 & 5.pdf
Title
Resolution to Approve a Construction Contract with Sorensen Gross Company LLC in the Amount of $482,205.00 for the Water Treatment Services Unit Flocculation 4/5 Gallery Improvements Project (RFP 25-48)
Memorandum
This memorandum and resolution requests approval to award a construction contract with Sorensen Gross Company LLC in the amount of $482,205.00 for the Water Treatment Services Unit (WTSU) Flocculation 4/5 Gallery Improvements Project (RFP 25-48).

The WTSU uses the flocculation process as a key step in water clarification and lime softening. Flocculation is a mixing process that allows particles to aggregate and form larger particles which are then removed through settling. The flocculation equipment is operated using motorized drive assemblies with various components in both submerged and non-submerged environments separated by a concrete wall. Flocculation Basin No. 4 consists of four (4) motor drives, and each drive includes a stuffing box assembly that provides a watertight seal where the drive shaft passes through the wall. In recent years, repair and maintenance efforts have increased, resulting in extended equipment downtime and frequent leakage through the stuffing boxes resulting in wet floors and drainage issues. The Flocculation Basin No. 4 stuffing boxes have reached the end of their service life and require replacement.

The scope of this project includes replacement of Basin No. 4 stuffing boxes and miscellaneous drive components, as well as improvements to Basin Nos. 4 and 5 gallery drains. Stuffing box assemblies will be purchased by the City due to lead times and operational constraints that limit the opportunity to complete construction. The proposed improvements are necessary to assure operational reliability of the City's WTSU infrastructure. This project is programmed in the City's Capital Improvements Plan (UT-WS-26-16).

Solicitation of Proposals
Water Treatment Services Unit (WTSU) staff supervised the development of plan...

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