Rainwater Collection and Landscape Irrigation

One of the many purposes of the inverted roof design is to catch rainwater both in a practical sense but also as a symbol of arms open up to the sky. For the first few minutes of a rainstorm, rainwater falling on the roof will be directed automatically to the city sewer. This allows the roof surface and downspouts to be flushed of any accumulating debris and dirt. When the flush is complete, a damper will divert the rainwater to a 550 gallon cistern that is located in the basement of the home. This is basically the same concept as Mayor Daley’s Rain Barrel Program, with the exception that the “barrel” is much larger and is closed off from the outside environment. The water collected in this cistern will be constantly agitated and circulated up to a water feature fountain in the courtyard. Collected water will be used to irrigate the landscaping around the house. Should the cistern become full, the system will detect this and overflow will divert to the city sewer.

Greywater Collection and Reuse

“Waste” water from the washing machine will be collected in a smaller, 35 gallon cistern, also in the basement, and eventually be reused to flush the two toilets in the home. Before this occurs, the water will be treated with chlorine, pass through two micro-filtration devices, and then be exposed to ultraviolet filtration. The code currently requires that all water supplied to plumbing fixtures be potable (drinkable) water, including toilets. Separate plumbing that is painted a different color (yellow) and labeled as non-potable is one of the requirements agreed to in order to use this system, as well as intermittent testing of the water delivered to the toilets.

WHY?

Our aquifers are DROPPING. You don’t hear much about it, but that’s not surprising with the current political climate and media distracted by Paris Hilton and Donatella Versace. For example the Ogalalla Aquifer stretches from South Dakota to Texas and accounts for 30% of farm land irrigation water in the United States. This aquifer is being depleted faster than it can be recharged. Just recently it was stated that the water levels of Lake Mead (the largest reservoir on the Colorado River System) are dropping at a rate that will possibly leave it dry as early as 2014. Municipalities in the Northeast are increasing the minimum lot size for new construction (to 12 acres in some cases!) to prevent local stresses on the ground water system.

Meanwhile, other aquifers are being contaminated with toxic chemicals and nutrients from industry and wastewater disposal (85% of superfund sites involve groundwater contamination!). As ocean levels rise with global warming, salt water may intrude into fresh water aquifers rendering them useless.

By reducing our water consumption we can preserve this precious resource and reduce the burden on local aquifers and sewage treatment plants (where our water goes when it goes “down the drain”).

Conventional wastewater systems generally are not environmentally responsible. Our wastewater goes to an energy-intensive sewage treatment plant where waste is metabolized by aerobic bacteria and solids are separated out as sludge. The sludge is hauled to a landfill and the water is treated with a chemical like chlorine and dumped into a nearby river, lake or ocean.

Rainwater Harvesting reduces pressure on our water supply AND reduces storm water run-off. Rainwater is usually quite pure and “soft” unlike most “hard” city water. In urban areas, consisting of mainly impervious surfaces, rainwater can’t filter down through the ground to replenish the aquifer and is instead transported through pipes (storm sewers) to rivers, streams and lakes. This contributes significantly to erosion and downstream flooding. 

In addition to Rainwater Harvesting, this home will have a minimized driveway width, and the driveway will consist of permeable pavers that allow rainwater to filter down to the ground below. The courtyard surface and pathways through the yard will be constructed of permeable pavers as well.

>>>>>OH! And are you aware that the water used to flush toilets can account for up to 40% of a home’s water use?

The following “low flow” plumbing fixtures will be utilized in the home. It is important to realize that the term “low flow” can be easily green washed. 2.0 gallons per minute (gpm) is LOWER flow, not low flow...

Showerheads: 1.5 gpm

Kitchen Faucet: 1.5 gpm

Lavatory Faucets: 1.5 gpm

Dual Flush Toilet: 1.1/0.7 gallons per flush

Low Flow Plumbing Fixtures