Facility upgrade

Facility upgrade plans

The Public Health Regulations of 2010 define the quality of effluents that must be produced in wastewater treatment facilities in Israel.

Association management has expedited the implementation of a general plan for upgrading the wastewater treatment systems at the facility in order to bring it to the level required by these new more stringent standards.

Association management also decided to provide a response to future population growth in the association's member cities. The total quantity of wastewater expected in the year 2030 is approximately 150,000 m³ per day.

A specification was prepared for an international tender, at the conclusion of which Hazen and Sawyer, a US company, has been chosen to plan the upgrade and adaptation to the new regulations.

General implementation of the plan by Hazen and Sawyer began in 2011. Following 15 months of planning, the company submitted a summary report that has been forwarded for approval by Israel's Water Authority, Ministry of Environmental Protection, Interior Ministry and Health Ministry.

According to this plan, upgrade of the treatment facility and its expansion will be performed while maintaining maximum operational flexibility, enabling additional improvement in effluent quality beyond that required currently by the regulations in the case where [even] more stringent requirements will be applied.

The principal recommendations for [facility] upgrade as appearing in Hazen and Sawyer's report focus on the following stages:

  1. Pretreatment and preliminary sedimentation
  2. Secondary biological treatment
  3. Tertiary treatment including filtration and disinfection
  4. Sludge treatment

Further detailing of the proposed upgrade is provided below:

  • Construction of a new array of mechanical bar screens
  • Construction of a new facility to remove sand and grit
  • •Execution of engineering improvements in the primary sedimentation basins
  • Construction of a new installation for aerating raw sewage
  • Replacement of the aeration system in the activated sludge basins with a system based on percolation instead of surface ventilators as exist today
  • Construction of a new activated sludge module
  • Construction of gravitational granular filtration basins with a 180 cm thick bed for filtering effluents
  • Construction of an effluent disinfection system using hypochlorite
  • Construction of an additional digester basin for the digester basins used in sludge treatment
  • Changes in the sludge thickening system to also enable primary sludge thickening in addition to the secondary sludge [thickening]

In Hazen and Sawyer's estimation, the proposed improvements will bring the treatment facility in compliance with all strict standards for wastewater treatment in Israel, with a view toward anticipated future changes.

The designer's estimated cost of this upgrade as detailed above is NIS 308 million.