Sister Grove Regional Water Resource Recovery Facility (RWRRF)

The Sister Grove Regional Water Resource Recovery Facility (RWRRF) was a multiple-phase, new wastewater treatment plant. Mbroh was engaged for electrical design services that included a power electrical distribution system and coordination with the power company to provide a new, dedicated power substation, new transmission lines and a power yard with transformers and pad-mounted switchgear. Electrical design included 15 kV main paralleling switchgear, protective relaying system, seven 3250 kW 15 kV generators, several primary and secondary unit substations, underground 15 kV loops, medium- and low-voltage MCC and switchboards, Arc Flash hazard analysis, short circuit study, and protective coordination study.

• The initial observation phase included an electrical study that resulted in a detailed electrical report.
• The backup generator system paralleled and synchronized with the power company’s two electric services to provide a redundant power source to maintain operations.
• Completion of the plant consisted of eight backup generator sets with a total capacity of 30MW.

One of the most important aspects of the project was the initial observation phase where Mbroh prepared a comprehensive electrical report for the new plant’s power distribution system. The report provided cost value analysis for main transmission power (overhead or underground) and emergency backup options. The scope of work included redundant lines to ensure operational integrity. Mbroh conducted numerous meetings with the power company to determine the feasibility of having two new substations and other viable options for a resilient, dependable, and redundant power source for the entire plant.