County Installs Stormwater Monitoring With Real-time Reporting

About the author: Gustavo Diaz is marketing manager for both WRT and Nivis LLC. For further information, phone 866-565-2906.

Located 30 miles northeast of Atlanta, Gwinnett County's Cultural and Civic Center now has a new look, due to a recent $90 million expansion project.

Holder Construction, Inc. of Atlanta was contracted to expand this facility. According to EPA's regulations and state laws, projects such as this require a NPDES Construction Activity permit.

To address the monitoring side of this compliance issue, Holder Construction regularly uses traditional stormwater monitoring systems. However, in this instance, they decided to implement both a traditional system and a newer system, created through a partnership of WRT and NIVIS LLC. Holder Construction did so in order to compare results and operational efficiencies between both types of units.

The main difference noted between the systems was that conventional samplers require a person to physically go out to the site to grab samples manually, whereas the newer system is Web-enabled and obtains samples automatically from a remote location. The newer system then generates real-time reports on the condition of the monitored site.

The monitoring equipment was operational for a period of four months. During this time, continuous site monitoring was realized. The WRT units were employed with a remote tipping bucket rain gauge that was able to turn on the sampling unit wirelessly and also sent the real-time rainfall data back to a secure web site hosted by Nivis LLC.

Likewise, the system monitored all samplers' functions such as batteries and system status on line. And it generated an automatic printable report suitable for EPA's regulatory purposes.

The multiple units that were used all reported back to a control access node that served as the data storage center. The access node transmitted the data collected from all of the units on the site.

One rain gauge controlled all the sampling units on site. The same technology can be used for multiple sites and would meet the regulatory requirements for proximity of rainfall gauges.

Holder Construction had full knowledge of the unit's performance at all times and was able to check information from any computer, Palm pad, or PDA.

According to Chip Hatcher, stormwater engineer from Mactec/Law Engineering and Consulting: "That is why the electronic monitoring and real-time data storage is so nice.

"With these units, savings per month are almost equal to the labor cost associated to the use of conventional samplers," Hatcher explained. Holder Construction plans to use approximately six additional units from WRT and NIVIS on their next project. The new equipment will replace conventional grab samplers.

The environmental manager for the project was Tim Ward and Daniel Alers was the site coordinator — both from Holder Construction Inc.