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For 21st century cities, when it comes to issues around water, water servicing and environmental protection, city managers are facing an increasing number of challenges as they seek to continue to provide these essential services to a growing population of urban dwellers in a sustainable manner.These challenges include aging/decaying infrastructure and the need to replace and improve this in the face of uncertain economies; emerging micropollutants and contaminants of concern (e.g.microplastics, pharmaceuticals and personal care products) and the lack of information on how to best deal with these with current technology; climate change as it affects water supply (droughts and floods), source water quality and the water environment and the operation of water servicing systems in the urban area; and the emergence of harmful algae blooms (HABs) and their consequent effects on urban water services and the source water environment (e.g.the development of hypoxic zones in large lake systems).The summer 2014 HAB episode in Lake Erie, which resulted in the city of Toledo, Ohio issuing a 'do not drink' tap water advisory to 500,000 residents, is a prime example of the changing environment in which city managers now must work, and also an example of a problem needing both short term and long term solutions.Given the general acceptance that point and diffuse source nutrient loading is the main driver of HABs, and the main diffuse source of nutrient loading from cities is stormwater runoff, it is reasonable to examine the urban form (typically comprised of hard,impermeable surfaces allowing little to no runoff retention and infiltration) to identify options for runoff nutrient control.One such option is the family of low impact development (LID) or 'green' infrastructure installations that mimic the natural hydrological cycle in urban environments, to retain stormwater longer on site for capture and reuse (of water and nutrients)or to allow it to slowly infiltrate to recharge groundwater resources.By reconnecting our urban surface and groundwater systems and by providing new methods for source water environmental protection, we can balance and link new and existing development with the primary goal of source water protection, as this presentation will demonstrate.