San Francisco in the USA now requires the treatment of grey water for the purpose of recycling. In Ireland also we permit the treatment and recycling of grey water for re use for toilets.
The water stress crisis in California is causing problems for this USA State. Climate change is causing lower snow accumulation on mountains in recent years. This is one of many reasons for their water crisis. Because of the rising temperature around the planet, climate change is unfortunately now also beginning to cause more widespread water shortages. California is now being forced to implement more sustainable water management policies.
For example San Francisco now requires large buildings developments of greater than 250,000 sq feet to install on-site grey water treatment systems for water recycling. Regardless of the cost to the user for water, the city planners in San Francisco are now making water recycling a requirement as part of the building planning conditions.
In Europe also we have the “Urban Waste Water Directive 91/271/eec” Article 12, 1 of this directive states that “Treated waste water shall be reused whenever appropriate” Unlike San Francisco buildings in Ireland are not required under planning to recycle water. It’s noteworthy however that those who wrote the text of the directive used the word “shall” rather than the word “may”. My view is that Ireland does have a legal obligation to enforce Article 12 as it is stated. I think it was very progressive of the old EEC law makers to be so prescriptive in using the word “shall”. Since we are still in the EU I think that the wording in the Directive makes a legal requirement on Ireland to change the planning law so that all new housing developments must treat grey water for the purpose of its reuse. Since for many reasons its not feasible to recycle the water that is treated from centralized municipal treatment systems; we must do it from grey water for all new individual buildings.
Dublin is itself a city with a very finite water supply; we do live on a planet with quite finite resources. The other important words in Article 12 are the words “whenever appropriate”. I believe that it is “appropriate” to recycle treated grey water at every house because it is more feasible that this treated water can be directed back for the toilets in the house. In contrast this can not be easily achieved if the water treatment only happens over a long distance away at the town’s municipal sewage treatment plant. As long as domestic houses predominantly dependent on distant centralized sewage treatment, these houses will be unable to receive or reuse recycled water.
There is now no obstacle to an Irish family wanting to install a mini reed bed in their own suburban garden to treat grey water and to reduce the family bill for water. Water recycling systems are permitted in Ireland. Have a look at Part H of the Irish Building Regulations for more information.