How Advanced Building Systems Can Offset Water Infrastructure Needs

Abstract

Water infrastructure requirements will be reaching crisis proportions in the coming years. Increasing urban populations, drought conditions due to climate change, and increasing EPA rule limits for drinking water contaminants set the tone for diminishing water resources. The American Society of Civil Engineer’s 2013 Report Card for America’s Infrastructure gives a grade of “D” for much of America’s drinking water infrastructure. The report states that capital funding has not kept pace with the needs for water infrastructure and that state and local governments will continue to assume the bulk of investment requirements in the coming decades. If we think holistically, however, many of these water infrastructure needs can be offset by how we address the historic view of buildings’ systems. The current premise is that buildings should simply “plug-in” to existing water infrastructure. The expectation is that a new building connects to a municipal water main and clean water flows and that waste water is flushed away and disposed of at a municipal treatment plant. This belies our growing institutional knowledge of holistic building design and urban development. Rather than becoming a point source load on water infrastructure, buildings are capable of becoming water resource generators. Precedent models for building based rainwater harvesting, reuse and treatment systems already exist, such as in the new San Francisco Public Utilities Commission building. This 277,500 square foot office building houses more than 900 employees, utilizes rainwater harvesting, and has an onsite “Living Machine” reclaiming and treating all of the building’s wastewater to satisfy 100% of the water demand for the buildings low-flow toilets, urinals and irrigation. If we couple these advanced building systems with model water conservation ordinances such as Tucson’s rainwater harvesting and gray water stub outs, we will rethink how buildings can actually offset water infrastructure needs.