Water Technology - Jan 2012

FEATURE Water infrastructure The building block of sustainable cities Cities must become more efficient in energy consumption as well as transporting and managing water 10 Water Technology January 2012 movement and heating costs that are not efficiently recovered today In addition water stressed areas are often energy challenged complicating the issue Investing for water infrastructure Governments across the world are being urged to increase spending to upgrade water infrastructure However public entities cannot take on this task alone The private sector also has a responsibility to invest in reliable and effective technological solutions for water analysis movement and treatment There are many good technologies already available to address these issues However a gap remains between the technology we have and what is actually used largely because of the gap between new technologies and old infrastructure and the inherent risk of implementation Two key areas of focus for this technology are reuse and recovery Thats because there is a lot of untapped efficiency in the way cities deal with water Up to half of all treated water that could be directed back to usage is lost As I discussed at the Forum we are treating all water to drinkable level for municipalities yet just one percent of water treated in municipalities is used for drinking and cooking the rest goes to things like lawn sprinklers and industrial use We must challenge ourselves to think of a future system that is more point ofuse focused rather than using the whole system for treating all water to such a high standard For instance a generally known concept for energy efficient buildings is Net Zero where a building is designed constructed and operated to require a greatly reduced quantity of energy to operate resulting in no net emissions of greenhouse gases We should consider expanding this concept to Whether we are brushing our teeth or watering our garden recent studies have shown that most of us take access to clean water for granted But it doesnt take much thought before you quickly realize that without it our modern way of life would quickly come to an end Its critical that developers and urban planners around the world factor this into their blueprints Each year The Atlantic hosts the Green Intelligence Forum bringing together the worlds leading authorities on energy and the environment to discuss issues at the forefront of sustainable thought This year I was honored to speak on a panel about creating the sustainable city of the future My fellow panelists provided perspectives on the financial socio political and infrastructure barriers to sustainability and the creation of more walkable urban communities These are communities in which people are far less dependent on their automobiles for getting to work enjoying leisure activities and running errands Such communities are not only more convenient but they also reduce energy consumption and cut greenhouse gas emissions Water infrastructure in urban areas Clearly we cannot discuss infrastructure sustainability or energy without discussing water both its transport and its treatment Urban water infrastructure faces many challenges including century old systems inadequate investment increased stress on systems and ever increasing treatment requirements due to emerging pollutants This has created a pending crisis in water and wastewater service delivery and increased groundwater contamination According to the UN urban populations are expected to rise 40 to 50 percent in the coming decades to 5 billion people and by 2025 two thirds of us will live in areas facing moderate to severe water shortages Proper methods of treating water are critical in sustaining the water supply in urban areas Yet urban population growth continues to outpace infrastructure investment Many large cities still lack treatment plants and some existing plants are unable to keep up with the number of people they are required to serve These outdated water treatment systems are not just a problem in the developing world The American Society of Civil Engineers gave the U S a grade of D for our drinking water and wastewater infrastructure One of the biggest consequences of exploding population growth in urban areas is increased pollution and the growing cost of energy required to turn dirty water into clean water Today roughly 15 20 percent of energy costs for an average city are for moving and treating water This represents the single largest portion of energy costs And when we look at individual commercial and residential buildings up to 50 percent of building operating costs can be related to water By Dr Johan Groen For more information on this topic go to www watertechonline com and enter keyword s Infrastructure water sustainability water supply