North Lee County
Water Treatment Plant Expansion
ADS Engineering provided electrical and instrumentation design in a design-build project and construction inspection services for expansion of a reverse osmosis water treatment plant. Process improvements included addition of a two RO skids with interstage pumps and improvements on the existing two skids; addition of two feed pumps and replacement of the existing three; addition of a new degasifier and scrubber with recirculation pumps, two new transfer pumps and two high service pumps. Changes in chemical feed systems came as a result of the new process equipment additions.

Project Highlights:
  • Design of new distribution switchboard and modification of the existing switchboards and MCCs to support the new membrane feed, interstage and high service pumps.
  • Design system for emergency electrical power with 500KW emergency generator and ATS switch for the existing switchboard for wellfield pumps.
  • RO Plant VFD Replacement & Electrical Room Improvements.
  • Existing chemical feed systems power and instrumentation modifications.
  • Expanding existing power monitoring system.
  • Implementation of variable frequency drives.
  • Modification to existing plant electrical system infrastructure to serve electrical systems added under the plant expansion.
  • Modifications to existing plant electrical motor control systems to integrate into the new control system.
  • Storage building electrical systems and lighting design.
  • Carbon dioxide storage facility and feed system.
  • Instrumentation design for the new RO skids and replacement on the existing two vessels.
  • Replacement of the existing instrumentation and addition of a new in chemical systems and compressed air system.
  • Design specification for the new surge tank and ammonia system packages.

Lee County Utilities


Carollo Engineers


Project design completed in 03, 2010

Project completed in 08, 2011

Total Project Cost: $20,000,000.00

Project Challenges

Previous electrical design supposed to include enough resources for the future expansion. During the preliminary expansion design, that fact was assumed to be true. When ADS started to be involved in the project, after thorough analysis, ADS discovered that previous design had not provide adequate power supply for the future expansion. The request was posed by the Owner and Engineer to ADS Engineering, to find a feasible solution for the problem. ADS Engineering came with a solution for additional power in the following way: the existing electrical power, coming from the plant for the wells, was removed from the wells. In that way, the significant load from the plant power network was taken off. The wells were provided with separate service and emergency generator power. The power gained by removing the wells made a room for the new load proposed in expansion.