Global trends and challenges in water science, research and management

Leaps and bounds have been made in areas related to river basin management on a global scale, inline with various technological advances of the 21st century. This chapter reviews 6 emerging trends related to water science, research and management

Watershed and river basin management

Leaps and bounds have been made in areas related to river basin management on a global scale, in line with vari- ous technological advances of the 21st century. We review six emerging trends related to water science, research and management. One of the main issues, which have come under the close scrutiny of the W&RBM SG, is international transboundary water management, where a position paper was produced, elaborating various issues related to the subject matter and was presented at the IWA 2010 Young Water Professionals (YWP) conference in Kuala Lumpur, Malaysia. Transbound- ary water management refers to water management proc- esses that straddle at least one political jurisdiction, either within a nation or across an international boundary. For example, 20 European countries depend on neighbouring countries for more than 10% of their water resources and 5% draw 75% of their resources from countries upstream (UNECE 2009). Global water withdrawals have tripled over the past 50 years. At the same time, flood events, caused by climate change effects; increased imperme- able surfaces, and anthropogenic use of flood plains, are increasing in both frequency and severity. It is estimated that almost half of the world’s population will be living in areas of high water stress by 2030 (UNESCO 2009)

Variation of an indicator of

Escherichia coli is an indicator of fecal pollution used to mandate recreational and drinking water quality. Concentrations of culturable E. coli following contamination of surface water are determined by three factors: dilution; cell attachment to particulate material and settling or resuspension in the water column; and the net rate of change in viability. This study evaluated the variability in the latter parameter, and how predictive variation in death rate was of culturable population densities at the time of sampling. Water samples (N=232) with varying levels of E. coli contamination were collected from 46 discrete locations in four watersheds across Canada over a three-month period and enumerated for culturable E. coli by membrane filtration plate counting (T0EC). Water samples were again enumerated following a laboratory 24 h holding period at 30°C in the dark, and the difference considered the death rate (ΔEC). Relationships of T0EC and ΔEC with environmental and water chemistry factors were explored using step-wise multiple regression. The model predicting T0EC indicated that stream order, total rainfall seven days in advance of sampling day, total phosphorus, and ΔEC were the most significant contributors. The model predicting ΔEC indicated that turbidity and NH3+NH4 were the most important contributors. A model suggests that the persistence factor is less important than dilution (i.e. stream order) in describing E. coli densities, followed by factors that influence the loading of E. coli into watersheds