In the near future, humanity will be challenged by the converging trends of energy depletion and climate change. It will be necessary for us to transition into a culture that consumes drastically less, and to shift away from the paradigm of perpetual material growth. As part of this transition, the means for securing food, water, energy, and waste management must be re-localized into people's home communities. As currently more than 50% of the world's population lives in urban areas, it will be critical to make our cities more sustainable.
As more and more often the word "sustainability" is being used as a marketing term, we are attempting to bring it back to its truer, original meaning: to live in such a way that the resources available to us today will be available also to an indefinite number of future human generations. This desire led us to create the Rhizome Collective in Austin Texas in 2000. The Rhizome was an old warehouse building that was converted into a demonstration site for urban sustainability, and a home base for numerous social work and activist organizations. On display were numerous ecologically designed systems that the public was invited to come and interact with and learn from.
Drawing from our years of experience at the Rhizome, we've written Toolbox for Sustainable City Living. It is a collection of skills, tools, and technologies usable by urban residents wanting to have more local access and control over life's essential resources. We advocate building sustainable infrastructure using affordable, simple designs that utilize salvaged and recycled materials. We believe sustainability should be something that is accessible to the majority of people in the world, and not just the wealthiest.
Below are several techniques that could be used by both urban (and non-urban) residents to live more sustainably.
Make a duckweed pond: Raise duckweed-- a tiny, floating, protein-rich water plant-- in a kiddy pool. Using only sunlight and nutrients, duckweed can double its mass every other day. The duckweed can then be harvested and used as a food for humans, chickens, and fish, or be used as a "green manure" for building soil fertility.
Build a floating trash island: Inspired by a natural phenomena, floating trash islands create habitat for plants and microorganisms to assist in purifying contaminated storm water runoff-- a major urban problem. They are made buoyant by floating debris, such as bottles and polystyrene, stuffed into a giant life-ring. Water plants are zip-tied onto the island's surface, and develop an extensive submerged root network that hosts water cleansing critters.
Cook with an old satellite dish: When the parabolic curve of a satellite dish is lined with a mosaic of mirror shards and aimed at the sun, it can focus the sun's rays onto a pot of water and bring it to a boil in minutes!
Construct a small scale biogas digester: Using a five gallon bucket, organic matter like plants, chicken manure, and dead leaves can be turned into methane gas. The gas then can then be stored and used for cooking and heating. Why pay money for natural gas when you can make it in your back yard?
Clean up contaminated soil with compost tea: Made with worm castings from a vermicompost box, compost tea can be used to help clean up toxic soils. The multitude of hungry microorganisms in the tea can help speed up the degradation of certain pollutants in city soils.