I'll let Wikipedia supply the full definition for greywater:

Greywater, sometimes spelled graywater, grey water or gray water and also known as sullage, is non-industrial wastewater generated from domestic processes such as washing dishes, laundry and bathing. Greywater comprises 50-80% of residential wastewater. Greywater is distinct from blackwater in the amount and composition of its chemical and biological contaminants (from feces or toxic chemicals). Greywater gets its name from its cloudy appearance and from its status as being neither fresh (white water from groundwater or potable water), nor heavily polluted (blackwater). According to this definition wastewater containing significant food residues or high concentrations of toxic chemicals from household cleaners etc. may be considered "dark grey" or blackwater.

In recent years concerns over dwindling reserves of groundwater and overloaded or costly sewage treatment plants has generated much interest in the reuse or recycling of greywater, both domestically and for use in commercial irrigation. However, concerns over potential health and environmental risks means that many jurisdictions demand such intensive treatment systems for legal reuse of greywater that the commercial cost is higher than for fresh water. Despite these obstacles, greywater is often reused for irrigation, illegally or not, in older rural construction, simple construction old and new, often consisting of nothing more than a "drain out back" (pipe pointed down the nearest hill). In droughtzones or areas hit by hose pipe bans, typically by manual bucketting. In the third world, reuse of greywater is often unregulated and is common. At present, the recycling of greywater is poorly understood compared with elimination.

For more information and technical aspects of greywater systems, consult Greywater.com. You will find graphical descriptions and photographs of greywater systems that make it easy to visualize how they work and methods of implementation. Be sure to browse the "Contents" links for more in-depth studies and a planning page for those who might be interested in implementing their own greywater system.

Caveat emptor: although greywater systems seem like a natural fit for Southern California's water crisis, getting permission to install one may not go as smoothly as one might imagine. The Los Angeles Times recently ran an article that describes the bureaucratic nightmare that installing a greywater irrigation system can become.

Tankless water heaters are a revolutionary idea in home water heating systems. They use less water, they use less energy, and they create less waste. Takagi is a Japanese company that has been around since 1946, creating their first tankless water heater in 1952. Takagi USA was established in 1995. I remember having a tankless water heater in my apartment in Spain in 1995. It was tiny and ran on very little gas and served all our hot water needs. It is very uncommon to find a house with a tankless water heater in the USA. Here is some information from the Takagi website that might turn some heads and change some minds about that big hulking water heater in your house:

Since a tankless water heater has neither a storage tank to keep heated all day, nor a pilot light, it burns gas only when you need hot water. This eliminates standby heat loss, which can be as high as 3-4% every hour for storage tank type water heaters. This higher efficiency can allow you to save up to 50% off your utility costs.

Tankless water heaters are small (2.2 cubic feet), light (60 pounds), efficient (a 0.81 to 0.94 energy factor rate), environmentally friendly (the only product of its kind to receive SCAQMD (Southern California Air Quality Management District) approval for it's low emissions (CO, Nox)), and functional (delivering between 200 gallons and 500 gallons of hot water every hour on demand). In addition to all this, through the year 2007, high-efficiency water heaters are eligible for a $300 tax credit. For more information about buying and installing a tankless water heater in your home, please contact abdi@ergo-eco.com.

Today I installed a Toto Aquia dual flush toilet in my bathroom. My old toilet was developing some serious cracks in the bowl and in the base, it was ready to be retired. I took out the old toilet and set about the business of installing the Aquia. This toilet has a dual flush feature, which means that it has two flushing buttons. One button uses .9 galllons (3.4 liters) of water per flush for liquids, the other flushes 1.6 gallons (6 liters) for solids. These dual flush toilets have long been available in Asia and Europe, but are just starting to make their presence felt in the U.S.A. For those of us living in drought-prone areas (such as Los Angeles and Southern California), this is good news. The water savings over the course of a year are impressive. According to the Los Angeles Department of Water and Power,

A dual-flush toilet allows the user to select either full or half flush. The amount of water saved with dual-flush toilets depends on the frequency with which the full and half flushes are selected. On average, dual flush toilets are estimated to use 20 % less water than standard efficiency 1.6 gallon per flush toilets.

By using a dual flush toilet, you are saving water without sacrificing the performance of an ultra-low flush toilet that uses 1.6 gallons per flush. While the installation of the Aquia is slightly different than that of a standard toilet, it is still surprisingly easy. I would recommend this product to anyone who is interested in conserving water and saving on their water bill. I think that the design of this product is very attractive as well, with a small footprint and clean, curving lines. It is definitely modernist in its design. If you are interested in getting a low-flush toilet for you home or apartment, please contact abdi@ergo-eco.com. Although the LADWP stopped giving rebates for dual flush toilets last year, you'll find that they are still competetively priced with conventional 1.6 GPF designer toilets. And they are doing much more for the environment and your pocketbook as well.