Water Infrastructure


Water infrastructure and treatment have a substantial impact on our environment. According to recent studies, the average person cites our ability to preserve our environment and provide clean drinking water as among the most serious problems facing the world in the future.

TWM is a recognized leader in water and wastewater engineering.  Whether a client has questions about regulatory compliance, advancing technology or environmental responsibility, whether their aging infrastructure is in need of repair, rehabilitation or replacement, TWM can help.  Our approach to every project is focused in cost savings, sustainability, and long-term value.

Our firm has provided facility planning and design services for a wide range of projects throughout the St. Louis area and the Midwest – meeting or exceeding EPA standards, NPDES permit limitations, and client demands for innovation, for a balance between initial and life cycle costs, and for ease of operation and maintenance.  Many of the treatment plants designed by TWM have been nominated as an “EPA Plant of the Year.”  And we have similar expertise in the design of wastewater interceptors, collection systems, lift stations, the separation of combined sanitary and storm sewer systems (CSOs), water towers and water distribution systems, and in securing and managing grant and loan funding for our clients.

TWM helps our clients navigate the potential minefields of regulatory compliance and project financing by tapping into the wisdom we have accumulated through more than 40 years of interaction with the federal, state and local agencies governing environmental projects.

  • Water Quality & Supply Studies

  • Transmission, Collection, & Conveyance Design

  • Booster & Pump Station Design

  • Sludge Treatment & Disposal

  • Enhanced Nutrient Removal Upgrades

  • Sewershed Studies

  • Electrical Engineering

  • Mechanical Engineering

  • SSO/CSO Evaluation & Elimination

  • Loan & Grant Management

  • Hydrogeological Studies

  • Modeling

  • Alignment Studies

  • NPDES Permitting

  • Financial Analysis

  • Subsurface Utility Engineering

  • Regulatory Strategies & Negotiations

  • Condition Assessments/Audits

“Timely, accurate, cost-effective deliverables. High quality work. Good communication with client. Responsive to requests for services and information.”

Jeff Slocum, Former Utility Manager, American Water Military Services

“The schedule prescribed by the IEPA required completion of design within 18 months.  For a project of this size, complexity and expense, TWM met the incredibly demanding schedule requirements. 

 I feel that TWM is an exceptional firm and would encourage other municipalities, especially those with CSO issues, to employ their services.”

Royce Carlisle, Director of Wastewater Treatment Plants, City of Belleville, IL

“TWM was always responsive – always available.  Promptly returned calls.  Shared concerns, concepts and asked thoughtful, specific questions.”

John Shrewsbury, Project Manager (retired), St. Louis MSD

“Over the past 40+ years, the City of Mascoutah has enjoyed working with TWM on many projects.  As a result of excellence in engineering, the City has been able to meet all of its infrastructure demands.  TWM has been a great partner with the City, always listening to our needs, bringing thoughtful, innovative, and efficient solutions to our engineering and surveying challenges, and providing prompt service.  I consider the company and its staff to be good friends of mine and of the City, and I give them my highest recommendation.”

Gerald Daugherty, Mayor, City of Mascoutah, IL

Wastewater Projects

Water Projects

Exceptional Service. Nothing Less.