Integrated water management

Balancing human water security and biodiversity integrity

Integrated water management represents a balance between two, sometimes competing, priorities: 1) human use of water resources, and 2) overall protection of the ecosystem. These two priorities can have divergent value systems, as can seen with some water supply stabilization initiatives that distort stream flow and destroy habitat, thereby negatively impacting biodiversity. However, there can and should be an emphasis placed on systems that simultaneously mitigate threats to both human water security (HWS) and biodiversity.

As a first step to marshalling energy and efforts to pursue integrated water management, Vӧrӧsmarty et al. developed a spatial picture representing threats to HWS and biodiversity. Threats were determined as an aggregate of 23 geospatial drivers (e.g. organic loading, fishing pressure, agricultural water stress, etc.) under four themes: catchment disturbance, pollution, water resource development, and biotic factors. The study captured that nearly 80% of the world’s population lives in areas where threat to HWS or biodiversity exceeds the 75th percentile i.e. the demand for integrated water management is widespread. The methodology is an improvement over previous studies in that it allowed a simultaneous examination of water security and biodiversity, had an enhanced spatial resolution structured on rivers and river networks, and estimated the benefits to HWS accrued from technological investments.

A key finding from the study, that follows from the estimate of benefits to HWS accrued from technological investments, is a relationship between GDP per capita and threat to HWS. The study found that countries with higher GDP per capita have the same level of incident threat to HWS, but this is then mitigated by technological investments. But interestingly, there is not this same investment made in rich countries to mitigate threats to biodiversity. This illuminates distinct pathways for developed and developing countries: 1) rich countries must mitigate threats to biodiversity without compromising water security, and 2) developing countries could “leapfrog” by pursuing integrated water management strategies to mitigate threats to biodiversity while also establishing water security for the first time.

The authors appear to conclude that what is needed is both more information and more money. (They even lament that we have globally fallen short of the UN goals for universal access to basic sanitation services even when the technical know-how and financial returns are there! Ha!) What does this big picture look like? How would they mobilize the necessary research and money?

References:

Vӧrӧsmarty, C. J., McIntrye, P. B., Gessner, M. O., Dudgeon, D., Prusevich, A., Green, P., … & Davies, P.M. (2010). Global threats to human water security and river biodiversity. Nature, 467(7315), 555-561.