German Technical Cooperation ( GTZ ) and the Stockholm Environment Institute formed , together with organizations active in the area of sanitation , an open network on sustainable sanitation to support the Year . The Sustainable Sanitation Alliance ( SuSanA ) , whose secretariat is located in Germany , aims to contribute to the achievement of the Millennium Development Goals by promoting sanitation systems that take into consideration all aspects of sustainability , raise awareness of sustainable sanitation solutions and promote those solutions on a large scale .