Much of the data the IBM system will be called upon to sort will be sensor reports on temperature, pressure, salinity, dissolved oxygen content, and pH levels, which will indicate whether pollutants have entered the river. Other sensors will be directed toward sea life, says Nierzwicki-Bauer, and will be used to study species and determine how communities of microscopic organisms change over time.

The exact number of sensors, their types, and their specific locations along the river have not yet been determined. But Cronin says that the sensors will easily number in the many hundreds, and the collaborators plan to develop new sensors along the way. IBM is also working to interconnect the sensors. According to Kolar, conventional network cables of various kinds, such as fiber-optic cables, will be used in some cases and wireless connections in others, depending on Beacon's research requirements. And since the Hudson River flows into the Atlantic Ocean, the river network will be designed with the idea of connecting it to oceanic observatory networks as well.

For Beacon, the project is an opportunity to extract new information from the ecosystem of the river and estuary in order to resolve environmental and policy issues. And what makes the Hudson an unusual subject for environmental monitoring--as well as a challenge to network--is that it is host to lots of human activity, says Cronin. The river is used by tankers, tugboats, barges, recreational vessels, and fishermen, and it's a source of drinking water for six communities. It is also an energy source for sewage treatment plants and industries along the river--in addition to being a home for marine life.

Once the monitoring system is in place, Beacon hopes to extend its efforts globally to create the same type of 24-hour monitoring system in developing countries where rivers are vital to local communities. IBM sees this as a unique opportunity to test and refine some of its advanced hardware and software, as well as develop new technologies for this particular application.

Culler is excited to see IBM involved in an environmental project. "I expect that you are now going to see quite a significant second wave of this [sensor network] technology. We were all really excited about it in 2003, and now in 2007 it is really mature enough that vision can come to reality."