Pilot testing compact process for largest wastewater treatment plant in the world. In 2001, the Hong Kong government awarded Black & Veatch a $5 million (HKD) contract to carry out pilot trials for secondary treatment of effluent prior to release into Hong Kong’s Victoria Harbor. The Harbor Area Treatment Scheme -- or HATS -- is a major effort to reduce pollution in this important harbor. Exceptionally tight space constraints and stringent standards dictate the need for a high-level, compact and innovative process approach. Managed from Black & Veatch's Hong Kong office and designed by the global process experts on the Black & Veatch PROTEUS team, this international collaboration also includes external partners Thames Water and Severn Trent.

Black & Veatch successfully defeated many other tenders to win the contract to conduct trials on compact non-BAF (biological aerated filtration) technology, using submerged aerated filters and tertiary denitrification filter technologies from Severn Trent Services. Securing the non-BAF pilot trial was a great achievement and was the result of a global effort to harness the best of Black & Veatch and selected partners.

A $2 billion endeavor. The specific characteristics of Hong Kong sewage, such as warm temperatures and high salinity due to flushing with seawater, make it necessary to establish on site design parameters before committing to a large-scale layout. Dry weather flows at the Stonecutters Island plant are around 1,739,000 m³/day (460 million gallons per day) but the available land for upgrading the plant is only 2.3 hectares (5.7 acres). An estimated investment of more than U.S. $2 billion will be required to complete the remaining collector tunnels and the treatment plant upgrade, making this one of the largest wastewater projects in the world.