Our Services

Water & Wastewater

Drinking Water Systems

An adequate and safe water supply is one of the fundamental components to improving the quality of life in our communities. We provide services to our clients in all aspects of planning and design for water treatment, storage and distribution improvements.

Our specialty areas include:

  • Drinking Water Treatment – Manchac Consulting Group can handle every aspect of your drinking water treatment needs from raw water suitability studies, to pilot studies to full scale design. The engineers at Manchac have provided engineering services on some of the largest water treatment projects in the State of Louisiana and Mississippi. Our experience ranges from small package type water treatment plants to conventional type plants to membrane treatment. Our engineers also have a wealth of experience in disinfection systems, including ozone.
  • Distribution and Transmission Lines – the planning and design of water distribution system infrastructure is a key service provided by Manchac. Our list of successful projects includes master plans, water distribution modeling, and small and large diameter water line design projects. Design of large diameter water lines can be complicated by crowded utility corridors, roads, railroads, drainage, sewer infrastructure, etc. Manchac’s engineers have experience with trenchless technologies that are utilized in large diameter pipeline construction. Design projects have included pumping facilities, transmission and distribution pipelines, wells, and water storage facilities. Our engineers have successfully worked on very complex water transmission main projects under emergency conditions.
  • Water Distribution System Modeling – Water distribution system modeling enables water system owners and operators to identify existing system deficiencies as well as forecast future system upgrade requirements.  A properly constructed and calibrated model not only assists greatly in achieving optimum system operation but also is an invaluable tool in rationally planning and budgeting for future growth scenarios and least-cost improvement of existing system components. Manchac Consulting Group engineers have experience developing distribution system models and using these models to assist our clients with the evaluation of their public water system.

  • Elevated Storage Tanks – Water distribution storage is provided to ensure the reliability of supply, maintain pressure, equalize pumping and treatment rates, reduce the size of transmission mains, and improve operational flexibility and efficiency. We understand the decisions that must be made in the design of a storage tank, including size, location, type, and expected operation. We focus on all design aspects including issues related to siting and permitting.


  • Licensed Operations Assistance – Manchac employees licensed operators in water distribution and water treatment. Several of our engineers are also licensed operators. We provide operational assistance to our clients at their water treatment plants as well as in their distribution systems. Our operational assistance is geared toward maximizing the use of existing infrastructure at the lowest cost. We focus on lowering costs associated with chemical and electrical consumption.
  • Grant and Loan Acquisition Assistance – we have assisted many of our clients in obtaining low-interest State Revolving Fund loans as well as acquiring grants. Manchac engineers have assisted their clients in Louisiana with SRF loans totaling over $200 million.
  • Chlorine Burns – The potential for bacterial regrowth and the formation of disinfection by-products in distribution systems are issues of concern for many drinking water utilities, especially those that employ the chloramination process. Water systems in some states are periodically required to perform a free chlorine “burn,” in which the system switches over to free chlorine disinfection for a few weeks out of the year in order to curb bacterial growth in the distribution system. We can assist you with the implementation of your chlorine burn program. Manchac Consulting Group is the first engineering firm in the State of Louisiana that has successfully implemented free chlorine burns, and we have worked closely with the State Department of Health & Hospitals in developing the protocol for the process.


Our engineers have planned, designed, managed construction of, and assisted with the operation and start-up of hundreds of wastewater plants and sewage pump stations. We have also designed thousands of miles of sewer collection. We have experience in all aspects of wastewater conveyance and treatment systems. Working closely with our clients we manage projects from small to large, ensuring that your long-term interests related to capacity and compliance are accounted for in the framework of feasible solutions.


Our engineers have designed and commissioned hundreds of wastewater treatment plants over their careers, ranging in capacity from .01 to 200 million gallons per day. Having this experience is essential when planning, designing and constructing a wastewater treatment plant – whether it’s a brand new facility or the upgrade of an old plant, our engineers have done it. Working with you to tailor the best solutions to site-specific conditions, we help you maintain affordable rates and minimize operating costs through efficient operation and management and achieve compliance through first-hand experience applying process controls.


From planning through operations, we offer a full range of services for collection systems that carry wastewater or combined stormwater/wastewater. We’ve designed gravity and pressure systems and thousands of miles of sewer pipelines, including interceptor sewers up to 96 inches in diameter and force mains up to 60 inches for open-cut or tunnel-in installation. Using data analysis and flow modeling technologies, we design combined, sanitary, and storm sewer systems that adequately manage peak flows. Our licensed operators and engineers establish maintenance programs to provide optimal, uninterrupted service and prevent overflows resulting from blockages.


  • Operations & Maintenance Support
  • State Certified Operation and Maintenance Training for license CEU Requirements
  • Electronic and Paper Comprehensive O&M Manuals
  • Development of Standard Operating Procedures
  • Development of Emergency Operating Procedures
  • Asset Assessments
  • Personnel Assessments

Civil Engineering Services


Manchac provides design, construction management and inspection of grading, drainage and paving projects. We can handle all aspects of new roadway planning and design, road upgrades and overlays, ROW acquisition, environmental assessments and impact studies as well as drainage impacts and drainage system design.

Manchac’s engineers ensure that all of our grading/drainage/paving designs are effective and efficient no matter how challenging the terrain while also complying with all applicable Federal, State, and Local regulations.  Grading and drainage design is crucial for both the immediate safety and long term viability of your project.  Proper grading and drainage design is essential to both seasonal precipitation as well as more extreme weather events.  The design must also ensure that erosion does not become an issue and that all roadways, structures, and adjacent properties will be protected from your design improvements.

Site Design

Site and civil design features are important design elements of any development. Our engineers work with clients to ensure the proper layout and design to satisfy your goals and to provide smooth and safe access, properly managing stormwater to prevent flooding and comply with permitting requirements, design of all necessary site utilities, and meeting all planning, permitting and zoning requirements.

Manchac’s solutions are integrated into the overall design of your property and include smart, innovative ways to maximize the facility’s operational flexibility. Manchac’s staff has years of experience designing and permitting site improvements for commercial facilities. Whether it’s civil engineering for site work and support facilities, potable water lines, sanitary sewer connections, site grading, surface water controls, or parking and access, Manchac can provide expert site and civil designs that meet your objectives.

Our Site and Civil services include:

  • Development of site layouts Civil/Site design engineering Floodplain delineation Surface water and stormwater management design Regulatory agency approvals Permitting


Coastal Engineering

IMG_4466mmManchac Consulting Group can provide feasible solutions for all your coastal engineering needs from conception through construction, including planning, design, permitting, bidding, and construction oversight. We provide comprehensive, sustainable solutions for our clients and offer total project delivery.

At Manchac we are committed to the preservation and restoration of sustainable coastal and estuarine systems. We strive to assist our clients in meeting their goals of restoring resources, enhancing economic stability, providing recreational benefits, and implementing flood and storm damage reduction measures.

Among the many coastal engineering services offered by Manchac are:

  • Marsh and Wetland Restoration
  • Erosion Control
  • Beach and Shoreline Protection
  • Living Shoreline Design
  • Coastal Permitting
  • Coastal Zone Management
  • Coastal Ecosystem Restoration
  • Construction Specifications
  • Sand Source and Borrow Area Investigation
  • Breakwater Design

Structural Engineering

  • Concrete Dams
  • Waterway Structures
  • Structural Dynamics
  • Soil-Structure Interaction Analysis and Design
  • Earth Support Systems
  • Braced Excavations
  • Deep and Shallow Foundations

Construction Management

Manchac engineers have experience managing construction projects ranging in cost of a half billion to as small as $50,000. Construction Management (CM) is the overall planning, coordination, and control of a project from beginning to completion. The goal of CM is aimed at meeting a client's requirement in order to produce a functionally and financially viable project.

No matter the cost of the project, without good construction management and inspection project quality, risk and costs cannot be assured. Manchac Consulting Group is well qualified to serve on your project as a construction management consultant, from both a design and construction perspective. We can provide a variety of construction services including complete oversight and management of your construction project to insure compliance with all aspects of contract documents. We’ve managed construction projects when we’ve done the design and we’ve managed projects that we have not designed.  We're prepared to take the lead in leading specific activities such as defining the management structure and responsibilities of the project management team, organizing and leading the implementation of project controls, defining roles and responsibilities, developing communication protocols and identifying elements of project design and construction which are likely to give rise to disputes and claims.

Construction Inspection

constrinspectionManchac provides Resident Construction Inspection services on all of our projects. Project inspection is provided to ensure that the Contractor’s work complies with the contract requirements. Many details of construction are not specifically covered in the specifications and are optional with the Contractor. Our inspectors verify that proper practices are followed and guard against use of unsatisfactory materials or faulty methods. Inspection is one of the most important elements of construction and contract administration. Good engineering design and properly prepared plans and specifications are essential for a quality end product. However, ensuring that specifications and drawings are adhered to depends largely on the inspector and his qualifications.

Master Planning

  • Wastewater Systems Master Planning

Louisiana Department of Environmental Quality SRF Loan Program

Louisiana Department of Environmental Quality (LDEQ) SRF Loan Program For information regarding the State of Louisiana’s State Revolving Fund Program please contact us. Manchac engineers have worked with the financial department of LDEQ for over 25 years and we have provided the engineering services for the majority of loans provided by LDEQ to municipalities. Click on the button below to access LDEQ’s website for information on the SRF program.

State Revolving Fund

Louisiana’s Clean Water State Revolving Fund loan program offers low-interest loans to communities for the construction or upgrade of wastewater treatment works and other water quality improvement projects. The program was created by the Clean Water Act Amendments of 1987 and the first two loans in Louisiana were made in 1990. Since then over $400 million in loans have been made to Louisiana communities and Manchac engineering staff has overseen over half of those loans - $223 million worth over the State of Louisiana.

  • Water System Master Planning
  • Department of Health and Hospitals DWRLF Program
  • CDBG Program Projects
  • GIS/Data Base Management


  • LDEQ NPDES Permitting
  • Section 404 Permits
  • Coastal Use Permits
  • DOTD Permits
  • Stormwater Permitting
  • Environmental Site Assessments
  • Reforestation Design
  • Wetland Delineations
  • EPA Consent Decree and Department of Justice Management Services