“The plan update provides a great basis for moving the sewer program forward in a logical progression and projecting capital needs for the next 30 years.” —Jerry Stewart

CTI was engaged by the City of Chattanooga, Tennessee, to update the Wastewater Facilities Plan for the Chattanooga regional sewer system. The original Chattanooga, Tennessee-Georgia “201 Facilities Plan” was written in the 1970’s and provided the “blueprint” for one of the largest regional wastewater systems in the Southeast.

The system studied in the update serves customers in 15 incorporated communities and unincorporated areas in four counties in Tennessee and Georgia. The planning area includes over 474 square miles with a 2005 estimated population of 367,000. The planning area was divided into four study areas, generally defined by the urbanizing areas within the drainage basins of major local tributary streams. Adding to the challenge were the size and complexity of the planning area and the need to develop infiltration/inflow estimates for numerous existing contributory wastewater collection systems.

The final plan update identifies over $36 million in needed system improvements over the next 25 years. Each identified improvement was selected after an evaluation of available system alternatives. The plan also identifies 18 service areas with unacceptable levels of infiltration/inflow. These areas will be targeted in the City’s CMOM program. Costs for eliminating the excessive infiltration/inflow from these systems are not included in the identified facility improvement budget.

Many aspects of the facilities plan developed in the 1970’s have been successfully implemented. The update examines development since that time and provides for continued expansion of the system in an orderly, cost-effective way.

While CTI provides primarily engineering design and construction phase services, we believe that planning for our clients in the early stages of their projects is one of our most important functions. CTI is committed to planning as the means to providing the maximum value for the client’s investment.  It is well understood that funds spent on planning and conceptual design pay the greatest dividends in controlling overall project costs (see graph).