Waterless Waste

Extremely low-flow toilets reduce water use.

  • Toilets use only two tablespoons of water mixed with biodegradable soap to  foam the bowl.
  • Toilets and urinals return air to the aerobic composters.

The Bullitt Center is the tallest building ever to implement a composting system. These aerobic systems have become very popular in one-story buildings and in places that don’t have access to sewer lines. The challenge was to develop a delivery system from the higher floors that would safely bring the waste down to the composters, while not overwhelming the composters with liquids.

When the toilets sense a user, they begin to emit foam. This foam, consisting of a biodegradable soap-like substance and about 3 tablespoons of water, slides down the vertical tubes, creating a low-friction lining to ensure all the waste makes the journey down to the composters.

In a standard toilet, sink, or urinal, the water in the trap (the “S” curve in the drain pipe) not only ensures that you get your wedding ring back should you accidentally drop it, but more importantly prevents methane gas from escaping through the drains. Since the Bullitt Center runs on composters and is not hooked up to the methane producing sewer system, it is safe to use just a standard pipe that goes straight down to the composters. This allows for the toilets to act as fresh air intakes, as air is drawn down into the composters themselves. One side effect of this system is that any dropped iPhones cannot be retrieved, so be careful!

Now that the Bullitt Center has applied a composting system to a multi-story building, the way has been paved for other office buildings to follow suit.

Next building feature: Waste Not – Composting Toilets