August 2024 Update

Lake Placid Dam August Project Summary

Date of Report: August 11, 2024

Recent Activities:

Since the last Report on July 12, 2024, the contractor has completed the Bay 1 downstream spillway slab pour to an elevation of 479.50'. In addition, epoxy dowels, rebar, hinge anchors, stoplog block outs, and form work were completed for the Bay 1 spillway to an elevation of 483.33' (the final lift). Bay 1 concrete placements to an elevation of 483.33' were started. The south embankment upstream dam armoring and installation of utilities have been started. The second of four sections of the Bay 1 spillgate was delivered to the site. Delivery of the remaining two sections of the Bay 1 spillgate (which are complete) was delayed due to weather issues, but receipt of those sections is expected soon.

Change Orders:

1. Change Order: A change order in the amount of $484,921.34 was approved to add a Gantry Crane to the Contract. The gantry crane will allow Lake Placid to set and remove stop logs as needed to maintain the new gates. There was no additional time added for this change order.

2. Potential Change Order (under negotiation): The existing concrete substructure had unexpected voids that required grouting. Sundt drilled several holes into the existing concrete substructure and filled the voids with grout to ensure the existing structure(s) would adequately support the new concrete structure poured on top of the existing substructure.

3. Potential Change Order: While excavating for dam armoring on the south side of the project, a Springs Hill Water Supply water line was damaged. The water line appears to be abandoned, but Sundt, Black and Veatch, and GBRA are talking with Springs Hill Water Supply to determine the remedy.

Schedule:

Previous Reports have mentioned that Sundt has been evaluating ways to recapture time lost from dealing with unanticipated debris discovered upstream of Bay 1. With approved change orders to date, the Substantial Completion date for Lake Placid is July 24, 2025, which is forty-two (42) days beyond the Substantial Completion date specified in the Contract.

It is important to note that the Substantial Completion date does not take into account the time needed to fill Lake Placid nor the final testing of the gates (as the lake has to be full in order to perform the final testing).

At the August construction meeting, Sundt revealed its plan to address the delay and recapture lost time.

1. Beginning Monday, August 12, 2024, Sundt will schedule an extra crew to work on the jobs. The extra crew will (1) alternate between the Placid and McQueeney sites, (2) work from 8:00 pm to 6:00 am, and (3) be used to tear down forms, tie rebar, and other work activities that can be completed at night. Pile driving and other activities that create an abundance of noise will be done during the normal daylight working hours.

2. When driving piles for the cofferdam in Bay 2, Sundt will be working the crews for longer shifts (but again, not during the nighttime hours).

3. Sundt will be spending increased time with their crews/teammates to examine lessons learned during Bay 1 construction activities, and how to best implement those lessons in Bay 2.

Other Items of Interest:

1. Steel Fab gate manufacturing remains on schedule to meet the needs of Sundt’s construction dates. Delivery of two (2) remaining quarter sections of the Bay 1 gate was delayed by weather issues but are scheduled to arrive at the site soon.

2. The Hydraulic Cylinder factory acceptance test (FAT) has been completed and the submittal is being finalized.

Upcoming:

In the next several weeks, we expect (1) installation of trench drain block outs, stop log block outs, and thrust anchors for the spillway slab to an elevation of 483.33'; (2) installation of north abutment epoxy dowels, side seal anchor locations, gate vent tubes, and rebar and concrete placements; (3) installation of center pier epoxy dowels, side seal anchor locations, gate vent tubes, and rebar and concrete placements; (4) continued dam armoring earthwork and concrete placements; (5) excavation and placement of rock riprap downstream of the dam armoring grade beams; and (6) cut off the Bay 1 cofferdam pilings around the first of September. The cofferdam pilings will be cut two (2) feet lower than the elevation of the upstream slab, which is an elevation of 483.33'.

Updated Substantial Completion Date: July 24, 2025