Lake Placid Dam October Project Summary

Date of Report: October 11, 2024

Recent Activities:

Since the last Report on September 13, 2024, the first structural concrete pours in Bay 1 for the center pier and north abutment wall have been completed. The structural concrete work for the second pour of the Bay 1 center pier and north abutment wall was started. The cutting of the Bay 1 cofferdam has started. The waler and spud pile for Bay 2 has been prefabricated and is ready to be installed. South embankment grading, utilities, and grade beams for dam armoring has continued.

Change Orders:

1. Potential Change Order: The Hydraulic Power Unit (HPU) layout is going to be revised to facilitate easier maintenance/access. This potential change order has been submitted to Sundt for review by Black and Veatch and GBRA.
2. Potential Change Order: Lake Placid switchgear replacement. The Lake Placid switchgear (basically a high voltage switch) located at the Lake Placid substation no longer works and must be replaced. More information will be provided once Sundt obtains pricing from their electrical subcontractor. [“Switchgear” is a broad term that describes a variety of switching devices that address controlling, protecting, and isolating power systems, and include devices to regulate and meter power systems and technology.]
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 still talking with Springs Hill Water Supply to determine the remedy.

Schedule:

As mentioned in the August Project Summary, Sundt has implemented various ideas to recapture time lost through the change orders to date (e.g. delays caused by unanticipated debris discovered upstream of Bay 1):

1. Sundt has continued to make up days lost from previous unforeseen obstacles by deploying an additional crew to work nights, prefabricating the waler and spud pile for Bay 2, and intending to drive pilings in Bay 2 for longer work shifts (not during the nighttime hours).
2. The current Substantial Completion Date is now June 30, 2025.
3. Sundt will begin to provide a broad time frame for when their work may impact the lake level and will communicate the specific date of lake level changes 24-48 hours beforehand. This information will immediately be provided to the WCID website and to CULP.

NOTE: With approved change orders to date, the Substantial Completion date for Lake Placid is June 30, 2025. 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).

Other Items of Interest:

1. Steel Fab gate manufacturing remains on schedule to meet the needs of Sundt’s construction dates. All four (4) of the quarter sections of the Bay 1 gate have been delivered and are present on site. All remaining steel sections of the Bay 2 gate are expected to be delivered to the site soon.
2. Oil testing of the Hydraulic Cylinders has been completed, and the results are being reviewed.
3. GBRA (with Black and Veatch) will investigate the specified coating associated with the gates' seams (where the 4 gate pieces will be bolted together).

Upcoming:

In the next several weeks, we expect (1) structural concrete lifts #2 and #3 (final lift) in the center pier and north abutment wall in Bay 1; (2) driving sheet piling in Bay 2 should commence the week of October 14, 2024; (3) lead abatement of the old gate in Bay 2; (4) demolition and removal of the old gate in Bay 2; (5) excavation of the area between the existing spillway and the cofferdam in Bay 2; (6) fish relocation downstream of the cofferdam in Bay 2; and (7) continued south embankment dam armoring earthwork and concrete placements.

Updated Substantial Completion Date: June 30, 2025

Recent Photographs of Construction Activity/Progress —