Under Globaltech’s Optimization and Improvements Design-Build Contract with the Palm Beach County Water Utilities Department (PBCWUD), Globaltech replaced the filter media in three filters at WTP 8. The existing media in these filters were over 30 years old.
This project includes the removal of the existing filter media (anthracite, sand, and gravel) from Filter Nos. 1, 2 and 3 and replacement of the existing media with new media. Only one filter was taken out of service at a time so that the WTP could maintain service to its customers.
Prior to beginning the filter removal, Globaltech cored the existing media in Filter No. 3, to determine if the media was calcified and if it would be difficult to remove. Result of the coring showed that the media was rounded but was loose and could be vacuumed out without additional handling.
Once the filter media was removed, an endoscope was used to examine the filter underdrains for debris. No significant clogging was found in the underdrains. The underdrain holes of each filter were drilled out to the original specification diameter.
Prior to the media installation, a coating contractor sand blasted the concrete walls and applied a waterproof coating to the interior of the concrete walls. The coating applicator was contracted separately by PBCWUD with Globaltech coordinating with their schedule.
Once the interior coating had cured, Globaltech proceeded with the media installation. Spare media from a previous project stored by PBCWUD was utilized in the first filter slated for media replacement. The spare media being stored was approximately 25% of the media need for one filter. Additional media was purchased as required based on the specification of the spare filter media in storage.
The filters had a fixed roof so the media was provided in 1 cubic foot bags which were carried (man handled) to each of the filters.
Palm Beach County Water Utilities