Nov 21

Lake Placid Dam November Project Summary

Date of Report: November 18, 2024

Recent Activities:

Since the last Report on October 11, 2024 —

1. the second structural concrete pour on the north abutment wall and the center pier was completed;

2. the third structural concrete lift for the north abutment wall and the center pier was started;

3. the Bay 2 cofferdam sheet piling was completed (except for the obstruction mentioned above);

4. the Bay 2 cofferdam excavation was started;

5. demolition of the existing gate in Bay 2 was completed;

6. demolition of the existing concrete structure in Bay 2 was started;

7. the maintenance bridge access for drill shafts was completed;

8. concrete armoring of the north embankment is ongoing; and

9. on the south embankment, rock riprap, concrete armoring as well as utility and electrical work is ongoing.

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. Team members are still waiting for pricing from an 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. Disposition of this issue remains pending.

4. Potential Change Order: Lake Placid operating pier obstruction with Bay 2 cofferdam piling (referenced in Item 3, above under “Recent Activities”).

Schedule:

1. The current Substantial Completion Date is now July 5, 2025.

2. The change in the Substantial Completion Date was caused by underwater obstructions found when driving the cofferdam pilings for Bay 2 near the existing operating pier. A concrete ledge was discovered, making it difficult to create a watertight seal against the operating pier.

NOTE: With approved change orders to date, the Substantial Completion date for Lake Placid is July 5, 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.

2. Hydraulic Cylinders factory acceptance testing has been completed and cylinders are anticipated to be delivered to the Port of Houston in December 2024.

3. Evaluation and resolution of an inquiry into the specified coating associated with the gates' seams (where the four (4) gate sections will be bolted together) is ongoing by GBRA (with Black and Veatch).

Upcoming:

In the next several weeks, we expect (1) placement of the third structural concrete lift at the north abutment wall and the center pier; (2) to complete excavation of the area between the existing spillway and the cofferdam in Bay 2; (3) placement of the Bay 2 concrete seal slab; (4) to begin south abutment pier widening below the existing slab in Bay 2; (5) to begin maintenance bridge drill shafts; (6) continued south embankment dam armoring, earthwork and concrete placements.

Updated Substantial Completion Date: July 5, 2025

Recent Photographs of Construction Activity/Progress —

North Abutment Wall and Center Pier Extensions (North Abutment Wall is in the background):