Waukegan Water System Enhances Resiliency

CHALLENGE: The City of Waukegan’s water system serves a population of 88,182, consisting of the City of Waukegan and three small adjacent communities. The water system includes two raw water intakes, a raw water pumping station, a water treatment facility three booster stations with ground storage tanks, and approximately 340 miles of water transmission pipeline.

SOLUTION: Operational Evaluation − The City of Waukegan needed an operational evaluation of its Water Plant and the water distribution system. The scope of services included an evaluation of the current operations of the WTP and determining if the water treated at the Waukegan WTP meets the U.S. Environmental Protection Agency’s (EPA) primary drinking water standards.

In addition, HR Green conducted an inspection of each WTP unit process as well as the three remote booster stations, noting the current condition and operability and noting any maintenance, reliability, or service concerns. The HR Green team developed a response to all 14 examples/accusations in the anonymous letter and completed a high-level condition assessment of the existing WTP and water distribution system for the ability to meet the primary drinking water standards.

Risk and Resilience Assessment − The City of Waukegan needed a Risk and Resilience Assessment (RRA) for its Water Treatment System. HR Green developed a Risk and Resilience Assessment for the Waukegan WTP’s facilities and a site assessment of all WTP facilities for existing security and countermeasures against malevolent acts and natural hazards.

The RRA includes assessing critical system assets for the most likely threat categories, determining vulnerability likelihood, and quantifying economic consequences and public health impacts resulting from asset damage. The final report identifies the Waukegan WTP’s highest-risk areas and will provide recommendations to improve resiliency.

Water Treatment Plant Capital Improvements − HR Green was retained by the City of Waukegan for the design phase, IEPA permitting, and bidding phase services for the Phase I Capital Improvements at the WTP. HR Green provided design services for the following:

Replacement of existing 24-inch and 30-inch raw water venturi flowmeters with electromagnetic flowmeters. The existing flowmeters were not meeting straight pipe requirements, so the proposed flowmeters had to be relocated. Four (4) butterfly valves were proposed to allow for flowmeter isolation for maintenance.

Installation of approximately 3,300 linear feet of chlorine line within an existing 24-inch intake for zebra mussel control.

Removal and replacement of two (2) 30-inch intake valves within a structure located in Lake Michigan. The project included the installation of electrical equipment and conduits necessary for valve automation. The City requested that the valves be automated in order to provide Waukegan WTP staff with the ability to safely operate the valves in winter months when access to the valves is dangerous. The project required careful selection of electrical components, conduits, and valves to withstand conditions of being submerged under water and with high concentrations of chlorine. The design also included the connection of the electrical components to the Motor Control Center located in the Raw Water Pumping Station. Work required coordination with specialized divers who are familiar with Waukegan’s intakes and intake structure.

Permanent isolation of an abandoned harbor intake to block flow from entering the WTP when Lake Michigan levels were high.

The project involved removing and replacing the existing reservoir vent covers. The design also included structural repairs to failing concrete at the vent pedestals and along access platforms. A construction sequence plan and an investigation of critical valves for successful reservoir isolation were also completed.