For The Helena, a compact system was designed that could be placed inside the building without disturbing residents. The solution included innovative use of a state-of-the-art, tiered membrane bioreactor, which allowed the division of system components that are normally joined. Modularizing the treatment process allowed greater flexibility. The modularization was enhanced by enclosing all membranes in tubes, on indoor racks, rather than in large concrete tanks typically used. In addition, given that the plant is located adjacent to residential apartments, the design had to address the problem of odor and noise control. Essentially, the developer demanded that the plant be entirely concealed to the building tenants.

The Helena successfully demonstrates that wastewater can be reused effectively—year-round—in an urban environment. By reducing water usage in this residential property and dense urban setting, where toilets, laundries, showers, plant watering and cooling towers make up the bulk of water consumption, the treatment plant significantly decreases the consumption of potable water and reduces the amount of wastewater sent to the city’s sewage system.