Urban Water Research Todd Rasmussen Associate Professor of Hydrology The University of Georgia, Athens and Pending Director, Urban Water Research Institute The University of California, Irvine

Atlanta, Georgia “the fastest-spreading human settlement in history" Time Magazine March 22, 1999

Ag/Poultry Forests Gainesville Lake Lanier Buford Dam

Urban Water Issues Stormwater Management Nonpoint Sources of Pollution Source Water Protection Water Conservation Wastewater Reuse Wastewater Infrastructure

Roles of Science Data Data collection - monitoring and experimentation Data storage, and dissemination - databases Information Data interpretation - forming relationships between data Information storage and dissemination - information systems Knowledge Understanding relationships - predicting outcomes Knowledge storage and dissemination - models Wisdom Using knowledge for the public good

Hydrology EPA/NSF Lake Lanier Water and Watersheds Project +Community beliefs and references change +Short- and long-term beliefs are different +Beliefs change in response to knowledge +Water quality can be characterized using the Rating Curve approach +Nutrient dynamics in the epilimnion and sediments control hypolimnetic O 2 +Water quality and habitat control community structure +Phosphorus-iron chemistry dominates nutrient dynamics Society Ecology

Water Research Strategy Identify relationships at the watershed scale –Public involvement: Defining Quality of Life –Prioritization: Best to Worst –Obtain information: “Soft” and “Hard” Develop solutions at the local scale –Feasibility assessments: economic, legal, engineering, ecologic, societal –Demonstration: education and outreach

Lake Lanier Strategy Watershed Analyses –Contaminant Rating Curve approach for TMDLs –Whole-Lake Loading Rates Implementation Strategies –Laboratory and Pond experiments –Simple BMP approaches (Meta Models) –Communicating results

Take Home Message Total Maximum Loads can be quantified –By using Rating Curves that correlate contaminant concentrations with discharge –Then establishing the concentration at mean discharge Preventing - reducing stormwater should be a priority –Sediment in stormwater degrades aquatic habitats –Stormwater contains nutrients, pathogens, etc.

Options to Reduce Nonpoint Pollution Stormwater Interception Strategies –Riparian and Floodplain Protection –Filter and Infiltration Strips –Headwater Ponds and Wetlands Source Minimization –Controls and Limits on Loading Rates –Land Use Restrictions

Stormwater Mitigation Conventional stormwater disposal practices –Stormwater channels, tunnels –Detention basins Onsite stormwater disposal alternatives pervious pavements raingardens constructed wetlands wet ponds drywells infiltration strips mulching riparian buffers greenspaces contour terracing

Onsite Stormwater Mitigation Surface Infiltration –Mulching, Vegetated Swales, Raingardens Subsurface Percolation –Drywells, Leach Fields Stormwater Retention –Constructed Wetlands

Vegetated Swales

Drywell

Impacts of Impervious Surfaces Impervious areas < 10% –Minimal impacts on aquatic systems Impervious areas > 25% –Complete loss of aquatic integrity Treecover < 40% & Greenspace < 20% –Increases stormwater runoff –Degrades water quality

Implementation Strategies Who Pays? –Downstream water users are willing to pay because it is cheaper to prevent contamination than to treat the contaminated water –Developers are willing to pay if all parties are treated equitably Who Benefits? –Landowners are paid to reduce nonpoint source pollution –Water users who obtain clean water –The Environment!

What is Needed A watershed management authority who –Collects fees from wastewater connections, septic systems, water supply systems, owners of properties with impervious surfaces –Pays land users to reduce historical inputs –Monitors watershed conditions to ensure that efforts are effective –Enforces existing laws for egregious violations –Supports environmental education

Needed … Model Ordinances –Stormwater Control –Riparian Buffers and Landscaping –Water Conservation and Grey-Water Reuse –Urban Forests and Green Space Other Measures –Conservation Easements (Land Trusts) –Transferable Development Rights (TDRs) More Ideas => Search for: –“Rules for Healthy Streams”

Water Resources Programs Measurement and Assessment –Water Quality and Quantity Effects on Aquatic Ecosystems –Hydromodification –Habitat Impairment Human Systems, Technology, and Policy –Education and Outreach –Demonstration Projects –Model Ordinances

How to Assure Success Data Needs –Examples of water quality treatment options Information Needs –Regional differences in effectiveness Knowledge Needs –Parameters or processes that are key to success Wisdom Needs –Relative ability for local communities to apply

Hydrology Society Ecology