Lake Placid Dam March Project Summary

Date of Report: March 15, 2024

Recent Activities:

The waler that supports the cofferdam sheet piling was lowered to final elevation. The old gates in Bay 1 have been removed. Soil anchors in the north abutment wall have been installed and have been successfully tested. Concrete was poured inside the “dog house” to provide added support for the location of the waler. Cofferdam excavation was started. Dam armoring is ongoing. Electrical work is ongoing.

[NOTE: The “dog house” refers to a concrete tunnel that runs the entire length of the dam. It is/was used to deliver water to the area underneath the old gates for raising and lowering the dam.]

Change Orders (pending):

1. Pending: Steel was previously ordered for the gantry crane bridge which will ultimately be installed over the top of the dam to set and remove stop logs. Upon recent field verification, it was discovered the steel that was ordered was too short and needs to be bent in a different configuration. This survey alignment adjustment and associated subsequences are being discussed by Black and Veatch (engineers), GBRA, Sundt, and Seguin Fabricators.
2. Pending: During the excavation of Bay 1, more debris and obstructions were discovered. Bay 1 has the original bypass gates that were used when the dam was originally built (circa 1927). Part of the concrete in the original bypass gates is obstructing the placement of the waler system. Black and Veatch, Sundt, Sundt's structural engineers, and GBRA are discussing possible workarounds/solutions.
3. Pending: The January 2024 flood event costs and time are being negotiated by GBRA, Black and Veatch and Sundt.

[NOTE: Information in Items 1 and 2 of the Change Orders section is unchanged from the February 2024 Project Summary.]

Schedule:

1. Sundt is continuing to evaluate ways to regain time lost from dealing with unanticipated debris discovered upstream of Bay 1.
2. Difficulties and obstructions on the existing dam in Bay 1 have caused issues with completely dewatering Bay 1. Sundt, Black and Veatch, and GBRA are working toward a solution(s) to these issues and should be reporting a proposal in the next couple of months.

Other Items of Interest:

1. Steel Fab gate manufacturing is on schedule. Steel Fab is the company building the new steel gates. (See pictures included with this report, below.)
2. The steel gates are scheduled to be delivered at the end of 2024 or the beginning of 2025.
3. The Hydraulic Pressure Unit (HPU) is being assembled. (See pictures included with this report, below.)
4. The HPU is scheduled for testing in late April/early May 2024.
5. Steel gate fabrication and assembly/testing of the HPU is inspected/overseen by GBRA, Black and Veatch, and Sundt.

Upcoming:

In the next several weeks, we expect (1) removal of the first section of the gate in Bay 2; (2) the placement of a two feet thick concrete working slab in between the old dam and the cofferdam; (3) to scan and layout existing dam rebar (to determine the location of existing rebar so dowels can be placed accordingly); (4) to drill and epoxy dowels and install rebar for the first foundation lift; and (5) to continue dam armoring activity (earthwork and concrete placements), and electrical work.

Updated Substantial Completion Date: May 14, 2025

Recent Photographs of Construction Activity/Progress —