Participants: MERI

A small white box attached to an old bridge in Berry's Creek contains enough solar powered equipment to monitor the water quality of the Hackensack River 24 hours a day, seven days a week. Three such calibrated water monitoring stations were deployed early in September 2004 by the New Jersey Meadowlands Commission. Another, deployed in October 2007, is located under the pedestrian bridge at Fairleigh Dickinson University with the remaining two stations located in Kearny and at Mill Creek Point. The "Yellow Spring Instruments" 6600 series multiparameter water probe and "Campbell Scientific" datalogging, solar power and communication equipment are utilized at each station. Every hour, the stations measure various aspects of water quality then transmit the information via cellular modem to the NJMC labs where results are updated on the Internet in "near real time". The stations are maintained twice each month during the fouling season (May - September) and once per month during all remaining months to ensure data quality.

Click on the image above to see the "near real time data".

The Master Plan adopted by the NJMC in January 2004 included goals for cleaner water and air. Data collected by these stations will help create a report card on the water quality of the Hackensack River, as well as help test theories on low oxygen levels. The stations monitor dissolved oxygen, water elevation, acidity, electrical conductivity, turbidity (the amount of particles suspended in the water), salinity and temperature.

Data Model Development
MERI is interested in the development of behavioral and forecasting models to better understand the quality of the water in the Hackensack River. As a result, MERI has asked the Mathematical Sciences Department of the New Jersey Institute of Technology to analyze the water quality data and develop time series forecasting models. The objectives of the study are to:

• Investigate the interrelationships among the seven variables within a site as well as the relationships of these variables with the external variables
• Develop models for water depth
• Develop models for forecasting each of the onsite variables as a function of the previous values of the same variable

The water quality data for Kearny and Mill Creek have been analyzed, along with the linear relationships among the variables within the site and variables found externally have been investigated as well. A harmonic model has been fitted for the water depth at Kearny that explains about two-thirds of the total variability. Tidal models have been fitted to estimate the water depth at Kearny/Mill Creek as a linear function of the water depth measured at the NOAA Battery Park station during the previous two hours. Finally, the time series models that have been developed for forecasting each of the seven site variables will be used for the quality control of these variables.