Wastewater treatment

Mott MacDonald has extensive experience in all aspects of wastewater and sludge treatment, encompassing all sizes of treatment plant, innovative and conventional technologies, and physical and biological treatment processes.

We also have extensive experience in biological nutrient removal, including modelling, and are skilled in advanced aspects of sludge processing including anaerobic digestion, associated heat recovery and energy generation.

We can manage all aspects of odour control, from initial optimisation of processes to minimise odour generated, to the installation of appropriate technology for the removal of odour. Our expertise covers both the development of new sites, and optimising and extending the life of existing sites.

Our expertise

  • High-level scope definition
  • Feasibility studies
  • Outline and detailed design
  • Operating and capital cost evaluation
  • Tender/contract preparation and analysis
  • Contract supervision
  • Site supervision
  • Commissioning support
  • Design evaluation
  • Due diligence
  • Process optimisation
  • Process operation

Our designs incorporate all conventional treatment stages, preliminary, primary, secondary and tertiary treatment. Environmental issues such as odour minimisation, containment, abatement, noise and visual aspects of treatment plant. Where appropriate, advanced treatment techniques and innovative design approaches are considered. We have expertise with advanced compact processing (lamella, biological aerated flooded filer, sequencing batch reactor, membrane bioreactors, hybrid activated sludge process.

Our aim is to provide solutions which are appropriate to our clients' needs. We consider projects on an individual basis to provide solutions that are consistent with discharge requirements and determine the most appropriate and cost-effective solution.

Our approach to wastewater problems put emphasis on understanding the site specific mechanisms which affect process performance, before determining the most appropriate solution. We can carry out treatability trials to assess the characteristics of a specific waste which helps determine which solution is most suitable.

Benefits to customers

We have a collaborative approach which helps us efficiently deliver effective solutions, tailored to meets clients’ requirements, by alliancing and partnering with our customers and their suppliers. Our joint ventures with Galliford Biwater, JV (GBM) and JN Bentley (MMB) have delivered a significant proportion of AMP3 and AMP4 wastewater capital programmes and have won many prestigious awards.

Key projects

Brighton and Hove Wastewater Treatment Scheme, England - We were the engineering consultant tasked with all aspects of the design development. This included site selection, design from feasibility through to detailed, planning permission and contractor supervision for a new treatment works to treatup to 225Mld serving a population equivalent of 300,000. A compact wastewater treatment process using lamella primary settlement and BAFF secondary treatment was selected.

Merstham STW Growth Project - Mott MacDonald as part of the GBM JV are delivering improvements to all stages of this 6Mld, 10,600 population equivalent, wastewater treatment works to comply with the AMP5 objectives. Where possible, value was added by the innovative use of existing site assets. Examples of this is the use of existing pump wells, existing storm holding tanks being converted to balance tanks, and the existing sludge holding tank being retained with the connection of a mechanical mixing system.

The Hague Wastewater Project, Netherlands - We provided technical process advisory services from the construction and commissioning stage through to financial close on this major pathfinder project. This project resulted in the modernisation of an existing treatment plant as well as the construction of a new one along with the introduction of nutrient removal facilities and sludge treatment. The project also comprises a 30-year concession for the design, construction and operation of a wastewater treatment plant at Harnaschpolder.

Esholt Wastewater Treatment Works, England - As part of the MMB JV we delivered improvements to the preliminary and primary treatment stages of this 280 Mld wastewater treatment works serving a population equivalent of 600,000. The solution included a novel power generation solution via a modified screw pump between the preliminary and primary treatment stages.

Swanage STW, Wessex Water - We were the lead designer on this project to double the existing membrane bioreactor capacity of Swanage STW. The works can treat flows up to 17.7Mld serving a population equivalent of 26,000. This installation required significant modifications to the process pipework, the electrical control systems and the chemical dosing system. All design work was completed using the Solidworks 3D design package. This software was used 'live' during the site progress meetings. This meant that progress wasfaster and the rigorous deadline was met.

We use necessary cookies to make our site work. We'd also like to set optional analytics cookies to help us improve it. We won't set optional cookies unless you enable them. Using this tool will set a cookie on your device to remember your preferences.

Reject cookies Manage cookies
expand-image mail-envelope icon-icon-linkedin-mmdv-green icon-close arrow-left icon-section icon-section-white arrow-down icon-arrow-down-sml icon-arrow-left-lrg icon-arrow-left-sml icon-arrow-right-lrg icon-arrow-right-sml icon-arrow-up-sml icon-champions icon-section icon-section-white icon-download icon-education icon-email icon-grid-view icon-language icon-link-to icon-list-view icon-location icon-login-register ec-icon-login-register icon-ec-apply-arrow icon-ar-apply-arrow icon-mm-icon-search-ec icon-minus icon-more icon-phone icon-plus icon-recently-viewed icon-search icon hash key-facts-corner-sash quote-underline social-icon-facebook social-icon-googleplus social-icon-linkedin social-icon-twitter social-share-icon-facebook social-share-icon-facebook social-share-icon-googleplus social-share-icon-googleplus social-share-icon-instagram social-share-icon-instagram social-share-icon-linkedin social-share-icon-linkedin social-share-icon-twitter social-share-icon-twitter social-share-icon-youtube social-share-icon-youtube sina-weibo MM-Shape01-Quote-Views MM-Shape03-Quote-Locations MM-Shape05-Quote-Projects MM-Shape12-Quote-Sectors MM-Shape13-Quote-Expertise MM-Shape14-Quote-About-Us MM-Shape14-Quote-Careers checkmark icon-expand-view icon-apply-now menu linkedin-mmdv-green icon-ad-close mail-mmdv-green icon-ad-menu menu-close ec-menu-close sphere icon-cookies icon-legal icon-registered-companies target rotate-screen video-replay-flat video-replay audio-mute audio-play