South County Regional Water Treatment Plant
12 MGD Reverse Osmosis (RO) Expansion, Collier County, FL 



Expanded water treatment capacity; ability to accommodate potential future increases in raw water salinity; use of excess concentrate disposal pressure to drive interstage pumping, reducing electrical energy demand by 450 horsepower; effective taste and odor control; larger normal and emergency power supply systems; potential for optimizing finished water quality by blending treated water from the existing lime softening system with that of the osmosis system.


The population of Collier County had increased drastically over a ten year period and the growth projected to continue which produced tremendous stress on both water and wastewater infrastructure. Collier County needed to increase the capacity of its reverse osmosis (ROP) water treatment plant and upgrade the automation with electrical reliability at the existing (LSP) lime softening treatment plant to meet the County’s demand.


Seeking a company with extensive water treatment plant expertise, this client chose Poole & Kent Company of Florida to expand an existing 8-mgd (million gallons per day) reverse osmosis (RO) water treatment plant to a total capacity of 20-mgd and upgrade the existing lime softening treatment plant’s automation with electrical reliability. During construction, Poole & Kent’s work included the following major elements:

ROP Expansion:

  • Six new high pressure 2-mgd RO treatment skids
  • Six new 400-horsepower vertical turbine membrane feed pumps with variable frequency drives
  • Six new membrane interstage turbo booster pumps
  • Four new cartridge filters
  • Six new degasifier systems and modifications to existing degasifier system
  • Two new odor control systems
  • New electrical service building
  • Four new 400-horsepower vertical turbine high-service pumps
  • Electrical service upgrades to support the new skids including new generator, pump drives, switchgear and substation
  • New finish water distribution piping and meter vault
  • Upgrade to existing FPL plant power feed
  • New standby generator #03
  • One new blend/transfer pump

LSP Expansion:

  • New chemical area electrical building #05
  • Replacement of existing degasifier system
  • Filter area electrical/control modifications
  • Electrical modifications to the electrical service building, including generator and MCC renovations
  • Control/electrical modifications to chemical building
  • Control/electrical modifications to sludge process building


Due to the critical nature of the ROP expansion phase, Poole & Kent Company of Florida built the six new RO skids on a fast-track basis. The company had all skids completed and in service within 14 months from the notice-to-proceed (NTP) date. The LSP expansion phase was completed within 20 months from NTP.


Originally built in 1984, the South County Regional Water Treatment Plant has undergone several expansions that have brought its current production to 32-million gallons of drinking water per day. Of these, 12 million are produced through lime softening water treatment and 20 million through reverse osmosis.



Poole & Kent Company of Florida

Collier County, FL

Hazen and Sawyer

Poole & Kent Company of Florida

November 2005 to March 2008

$26 million


Poole & Kent Company of Florida - Technical Solutions, Relationships, Quality Service, Value Engineering, Experience, Project Schedule & Coordination, Expertise









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