RedfishOutletTrailBridgePreBidMtgSummary.pdf

Redfish Lake Outlet Trail Bridge Construction Pre-Bid Meeting / Site Visit (May 20, 2021, 11:00 AM)

Solicitation # 12-40LT-21-R-0003

Meeting notes shown in italics under 4. Questions? section below.

1. Introductions

2. Project Overview

Remove existing two-lane multi-span treated vehicle bridge and replace with new narrower single span treated timber trail bridge.

Remove water/irrigation piping from existing bridge and install new waterline and roller/hanger support system.

Remove existing asphalt approaches to former vehicle bridge and replace with new asphalt approaches.

3. Important Dates & Anticipated Work Schedule

June 21, 2021 – anticipated start date for administrative and construction preparation tasks.

September 27, 2021 – anticipated start date for on-the-ground construction (up to 20-feet from either side of existing bridge abutments).

October 1, 2021 – date in which existing bridge removal and all other work can begin (fish window) June 30, 2022 – project end date.

Summer, 2021 Complete bridge superstructure design/review/approval, prepare shop drawings, and following review/approval, have new timber bridge structure fabricated.

Prepare/review/approve other required material submittals and complete other relevant administrative tasks in preparation for construction.

Fall, 2021 Remove the existing asphalt road/trail surfacing material from the bridge and from both approaches.

Dismantle/remove the existing bridge structure including supporting abutments, piers, railing, underlying waterline and irrigation piping, etc. and dispose of offsite.

Protect and stabilized streambanks at former abutments.

Install new treated timber abutments, new treated glulam girders/diaphragms, and backfill approaches.

Spring, 2022 Install remaining treated timber bridge system components.

Install new waterline including bridge roller/hanger support system.

Construct trail approaches, place asphalt surfacing, and complete final grading/restoration of slopes.

Clean site.

4. Questions?

The hope is that the new bridge girders get installed this Fall but that’s not a must. The new bridge substructure must be installed along with riprap protection and backfill for sake of rendering the streambanks stabilized prior to the increased spring stream flows.

When commencing work in the Spring, 2022, the water system work needs to be completed prior to other improvements so that the water system can be energized for the upcoming field season. This will be clarified/updated on Amendment #1.

What are allowable work hours? These are outlined under Section 108.

Do campgrounds close in the Fall? Yes, the water system begins going off-line between mid/late

September which also corresponds to when campgrounds begin to close. Some campgrounds stay open into October.

Provided overview of bridge removal effort from Redfish Phase One project from 2014 – 1) Asphalt was removed along with timber railing, curb, and other elements; 2) the bridge superstructure/laminated deck was cut into nine pieces (three per span) and those were removed and hauled off on flatbed trailers; 3) pier supports were removed from stream with crane; 4) timber abutments were removed. Key consideration with this is that all dirt and debris from bridge removal effort must be captured with tarp or similar to avoid falling into the stream.

Overviewed riprap removal/salvaging effort. Existing riprap shall be salvage and re-used following the installation of the new bridge substructure. Supplemental riprap is available from the identified riprap source.

Identified riprap source location as approved location for contractor personnel camping.

Can riprap source be utilized for job trailer and can job trailer stay through winter shutdown? Yes New bridge superstructure and waterline roller/hanger & expansion fitting designs are the responsibility of the Contractor. Also mentioned that the new girders are depicted as single full-length members, so if splices are required, then that splice design is also the Contractor’s responsibility.

Existing asphalt path on eastside bridge approach has a 2” thickness, so construction traffic on that side of the bridge will likely need to access the east bridge approach via the former roadway that was rehabilitated as part of the Redfish Phase Two project from 2018. If that former roadway is utilized, then it will need to be rehabilitated to match existing conditions following completion of the work.

Can east approach construction materials be stockpiled near eastside bridge approach for use in that area prior to removing the existing bridge? Yes.

How will the new waterline on the bridge be winterized? The new waterline supported by the bridge will follow the bridge camber to render half the flow draining toward each bridge end. There is an existing drain located on the east approach, so it’s assumed this flow will reach that. A new drain is proposed with the project for the west approach.

When does the snow usually melt? Typically, this occurs around the beginning of May. Informed group that there is a webcam in place to check status (Redfish Webcam).

Is instream work required? No instream work is anticipated or allowed except for salvaging existing riprap from each abutment and placing salvaged/supplemental riprap for protection of the new bridge abutments. Equipment is not allowed in the stream.

Will existing woody debris in stream need to be removed? Following removal of existing bridge, any debris that was hung up next to the existing bridge pier supports will be allowed to float downstream.

Removal by Contractor will only occur if debris inhibits the Contractor’s ability to perform work.

Is there any subsurface or Geotech information available to know what to encounter when constructing the new substructure elements? No, but from past experience from previous projects, rocks that are encountered are usually boulder/cobble in nature and typically match those on the surface. Solid rock is not anticipated. Contractor’s shall also anticipate the need to dewater.

Identified approximate asphalt removal limits on west approach and noted required fill removal for sake of transitioning from former wide road template to new narrower trail template.

Outlined material sources and noted that substructure backfill material will likely need to be imported to ensure clean material meeting the gradation requirements is achieved.