2007/06/20 Council Agenda Packet

Ia iz • Review basic project requirements and constraints, including project objectives, critical design issues, operation requirements of water system while Reservoir No. 3 is drained, construction access, project schedule, and other issues. • Visit Reservoirs No. 3 and No. 5 sites. Access into Reservoir No. 3 is limited to the area immediately adjacent to the cover access hatch and therefore visual observation is limited. Observe interior structural features inside (drained) Reservoir No. 5 that are similar to Reservoir No. 3. • Discuss and document inlet/outlet pipe configuration for Reservoir No. 3. For budgeting purposes, it has been assumed that two MWH staff will attend the meeting and site visit, which will last approximately 8 hours. 1.3 Design Meetings. Conduct up to two meetings with City staff to review reservoir operations, construction issues, liner connection to column footings, liner rehabilitation options located at inlet pipe, liner material selection, design/specification decisions, project schedule and other design issues. For budgeting purposes it has been assumed that two MWH staff will attend each meeting (up to three hours each) at City's office. A meeting summary documenting action items and key decisions will be prepared and distributed within three business days after each meeting. 1.4 Design Criteria Summary. Prepare a Design Criteria Summary Technical Memorandum.(TM) documenting key design decisions. The TM will consist of one page of text and present the design criteria and issue decisions in table format. The following key design issues will be presented in the TM: • Liner material alternatives: polypropylene or Hypalon®. • Appropriateness of installing the new geomembrane liner directly over the existing liner located on the reservoir concrete side slope. • Options for connecting the geomembrane liner to the base of the concrete column footings. The options include 1) locating the batten bar anchor system on the concrete reservoir floor around the footing perimeter; and 2) locate the batten bar anchor system to the vertical face of the footings above the concrete reservoir floor. • Up to three design concepts for improving the existing liner design located beneath the inlet pipe to prevent future liner damage caused by hydraulic energy from inlet reservoir flows. Design concepts will be developed during the Kick-off meeting. • Construction access and staging requirements and constraints for the reservoir site and interior of the reservoir structure. • Construction schedule and sequencing constraints necessary to allow the City's continuous operation of flow through the Reservoir No. 3 bypass line and evaluate the impacts to the Re- Lining construction work. • Evaluate using Liquid Boot (or similar product) as a liner for the concrete floor and column footing surfaces in-lieu of using a geomembrane liner. Evaluation will include the following: 1) Contact up to three separate municipal owners whom have used this product to line potable water reservoirs in similar situations; 2) review adequacy of waterproofing the concrete panel joints and 3) environmental installation requirements, installation duration and compatibility with other materials such as geomembrane liners. Submit five copies of the Design Criteria Summary TM to the City fifteen working days after NTP. The City will provide a single set of consolidated review comments to MWH within four working days of receipt. MWH will incorporate City comments, and issue the Final TM. Decisions 00 City of Everett Exhibit A—Scope of Work Engineering Services for Reservoir No.3 Re-Lining Project Page 2