|The City Council authorized construction Contract 14965 with MH Civil Constructors, Inc. of Amarillo, Texas on March 24, 2020, with a contract price of $15,000,000 and 600 calendar days for completion of the construction of the North Water Treatment Plant (NWTP) Improvements Phase III and the South Water Treatment Plant (SWTP) Uprating Improvements. The Notice to Proceed was issued on May 27, 2020, and the project start date was June 15, 2020.
The City Council authorized Change Order No. 1 to Contract 14965 on March 9, 2021, which resulted in an increase of $671,900 to the contract price, and an increase in construction time of 58 days.
Proposed contract modifications in Change Order No. 1 included:
• adding additional rebar post-design to the new backwash basin at the NWTP;
• replacing Filter 16 media and underdrains at the NWTP following a filter blowout that occurred during the project;
• replacing two valves on the filter backwash system at the NWTP that were discovered to not be in working condition prior to the project start; and
• removing and replacing corroded metal baffles inside the plate settler basins at the South Water Treatment Plant (SWTP).
Change Order No. 2 will incorporate one proposed contract modification. The modification includes addressing the existing pipe supports for the 36-inch Concrete Cylinder Pipe (CCP) inside the sedimentation basins. Upon blasting, significant damage to the existing aluminum pipe supports was discovered; therefore, it is recommended to replace the pipe supports with a concrete corbel design that will improve the durability of the pipe supports. These modifications improve the capacity and reliability of the City's Water Treatment Plants.
This Change Order will increase the contract price by $149,224, with no change in construction time, resulting in a revised total of $15,821,124, with a contract time of 658 days.