Confined space entry presents significant hazards to municipalities working with below ground pump stations.
The flooding of below grade stations can lead to an emergency service call and cause catastrophic damage of system equipment, often costing owners greatly for expedited repair or even replacement.
More importantly, confined spaces present health threats to entrants. Atmospheric conditions such as lack of oxygen, dense gases and additional dangers force operators to follow stringent guidelines when entering confined spaces to ensure adverse health consequences are avoided.
At Metropolitan, we believe upgrading below ground pump stations with above grade solutions most effectively protects both the investment of systems and the lives of equipment operators.
While eliminating confined space entry entirely should be the end goal, our above grade solutions can significantly reduce the frequency workers must enter confined spaces. With a comprehensive submersible pump retrofit, the need to enter confined spaces can be completely eliminated.
An illustration of our ability to retrofit below ground pump stations can be demonstrated by the work done in the village of Chicago Ridge, IL. Faced with severely damaged system equipment, including pumps and controls due to a below ground vault flood, the village turned to Metropolitan to provide a quick solution.
“During a heavy rain event, a sump pump situated in the pump station’s dry pit malfunctioned allowing sewage to flow from the wet well to the dry well, causing the dry well to flood,” said Metropolitan municipal salesperson Keith Girup. “Unfortunately, due to the dry well flooding, the customer’s investment, including pumps, controls and power distribution equipment, was completely submerged underwater and caused irreparable damage. An immediate emergency retrofit solution was required.”
In order to get the pump station up and running in an accelerated fashion, the village elected to bake dry the pump motors, which were eventually placed back into the below ground station. To reduce the occurrence of entering the below ground confined space and protect the investment of system controls, Metropolitan supplied the village with an above grade control traffic box.
Included with the traffic box package was Metropolitan’s new LMS II level management system. Completely off the shelf and designed to provide customers with vital SCADA features at a cost-effective price, the LMS II control package played a key role in supplying the village with a prompt solution.
Developed by Metropolitan’s research and development team, the LMS II is a menu-configurable, constant speed pump down level controller, allowing one to three pumps, single/dual level transducers, 0-20 mA flow meter input, and a completely redundant float backup controller. Seal fails and thermal inputs are available by default.
The LMS II can be accessed directly at a lift station on its easy-to-use color touch screen interface or controlled remotely via a laptop. With the inclusion of an internet connection or cell modem, and Metropolitan’s MetroMail™ alarm-dialing system, users can receive alarm notification via any SMS text or email compatible device.
“In developing the LMS II, our goal was to create a standard program with options that covered 90 percent of all lift station applications,” said Metropolitan research and development manager Wayne Barkley. “This program gives us a systematic solution to designing lift station controls, eliminating much of the excessive labor associated with the design, engineering and programming of controls. Right out of the box, this system can serve many stormwater and sanitary stations with one program.”
Girup said the LMS II can fit a variety of lift station uses and is especially advantageous for consumers who seek to one day implement a master SCADA or building automation system. The LMS II can also be used in commercial applications.
“Each LMS II unit can be defined as a distributed SCADA system, providing substantial benefits to owners who may have plans to one day build a centralized SCADA system with master computer,” said Girup. “The LMS II has the capability to communicate with owners via email and/or text message, and can also be viewed via the internet for current system information, as well as historical data trends. The LMS II allows for a phased distributed SCADA approach, which can ultimately be tied into a more sophisticated centralized SCADA system at a future date.”
In addition to the traffic box package, Metropolitan also included a flood switch for installation into the dry well to notify operators via their SCADA system in the event of another dry well flood. This allows for a rapid response in the effort to prevent further flooding of the pump station’s dry pit.
Girup said this project is likely to serve as phase one of an extensive retrofit of the entire pump station. Phase two would be the installation of submersible pumps into the existing wet well, which would allow for the complete elimination of the confined space.
“Metropolitan is typically able to provide customers with an à la carte solution,” said Girup. “When the resources to fund a complete retrofit upgrade of a pump station are not feasible, we have the ability to work with the customer’s budget to supply the equipment and services that are most practical for the owner and application at a given time.”
This, combined with our 24/7/365 emergency service assistance, led to the successful, expedited upgrade solution for the village of Chicago Ridge.
“This project is a perfect example of why municipalities should start budgeting to upgrade existing dry pit pump stations of this type,” said Girup. “Fortunately, we were able to respond to the customer very quickly. In the coming years, I anticipate that many municipalities will continue to call on Metropolitan for a phased retrofit upgrade solution to eliminate confined space, below ground pump stations in the effort to avoid emergency circumstances.”