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The East Bay Regional Park District (EBRPD) is designated a special district by the state of California. It is the largest special district in the U.S., with more than 90% of its land protected and operated as natural parklands.
EBRPD is responsible for 1,745 sq miles of land, encompassing both Alameda and Contra Costa counties on the eastern side of San Francisco Bay. It manages 29 park trails, 65 parks, camping and recreation areas, lakes and lagoons, wilderness, shorelines, fishing docks and preserves as well as education centers and conference facilities.
For such a large and widely spread district, effective management of water and wastewater is critical. The supply of potable water—and wastewater collection and treatment—needs constant monitoring and control across all facilities to prevent problems and avoid any possible environmental issues.
New Five-Year Plan
“We used to have an amalgam of antiquated and largely incompatible equipment to control 38 pumping stations. Some wastewater pumps dated back to the 1970s,” said Richard Guest, water utilities maintenance supervisor for the district. “Two years ago, I developed a five-year plan to modernize all wastewater plants and pump stations. The objective was to develop a highly reliable, centralized control system that is simple to operate and can accommodate SCADA with minimal adaptation.”
“However,” he continued, “I had to consider our many employees who transfer within the district on a regular basis, and a significant number of part-time and seasonal employees as well. It became crucial to standardize every panel so that employees would not have to relearn how to operate unfamiliar equipment when they moved around. We also wanted a simple, user-friendly configuration. Simplicity is key to a well-managed, smooth-running operation.”
In the past, the district’s water and sewer pump stations had no communications ability at all. Visual inspection was the only way to identify a problem at a pumping station, and any failure had to be addressed on site.
After extensive review of pump control systems, MultiTrode’s Multi-Smart pump controllers were selected by EBRPD for their proven reliability and modular expansion and open interface capabilities. Other positive considerations included easy installation and simple, intuitive operator controls. The controllers combined ease of use with advanced functionality for up to nine pumps.
During installation, no design modifications were required, the product was user-friendly and easy to understand and no setting or programming adjustments were needed. “The installation was the easiest thing I ever did,” Guest said. “I took the unit out of the box, wired it up, turned it on and it ran. The initial startup screen came on, asked me four or five questions and gave me a choice of options depending on how I wanted to use the equipment. All I had to do was select an answer and confirm.”
With MultiSmart controllers, there are several fail-safe features built into the system. For instance, the controller has alarms and pre-alarms, where an operator is notified prior to an alarm. The system is not limited to only look at things that have failed. It is also able to pinpoint potential failures and other problems before they happen.
“Suppose the sewage level has risen far enough that a pre-alarm is tripped,” Guest said. “Once the operator is alerted, he can log onto a system computer and check the station in question. It’s not in alarm mode yet, but it’s past the point that an operator would normally be comfortable if he were standing there watching the station.”
District staff controlling the pump stations are able to log into a station and take a critical look and see if a pump has failed to start, or a pump is starting too fast, or even if the sun is heating the inside of the control panel and causing a component to malfunction. Any of these conditions would prompt a pre-alarm signal. The controller not only sends a signal, it is capable of identifying the problem.
As part of the five-year plan, EBRPD is preparing for SCADA to go online in the fall. With SCADA interfacing with MultiSmart controllers, a centralized network will be able to reset, troubleshoot and otherwise correct the majority of problems directly from a remote location computer or a centralized computer. With SCADA, the operator can see what the problem is, what caused the problem and decide to either reset it from the base computer or dispatch someone to the station for service. The dispatcher can tell that person exactly what he or she is going out there for, what to do and what to bring.
Cost Savings & Flexibility
EBRPD has pump control stations all over the 1,700 sq miles it covers, and sometimes it takes up to an hour and 20 minutes to reach a location.
“The real cost saving is not in the purchase price or installation cost, but on the operational and maintenance side. The new pump controllers have greatly reduced the need for emergency responses,” Guest said. “Now the stations are checked once a week, and it takes less than 30 minutes. In fact, we are to the point where we almost never have emergency calls on our wastewater pumping stations. This results in much less overtime. In the past, when we had a problem, someone had to go quickly, regardless of the time or day.”
Performing predictive maintenance used to be a manual operation. Now tracking things like bearing and field life in station pumps is accomplished systemically, without estimations or calculations from the operator. The controllers are capable of accommodating up to four different software changes to the control panel by making simple software configuration changes with little more than a flash card.
In a parks and recreation district, flexibility in pump station control is an important issue. Sudden population shifts at the park may require a station to perform differently or that alarm criteria change to accommodate a critical upcoming event. In the past, the pumps were either on or off, and the same applied to the alarms.
The new controllers also allow stations to communicate with each other. This is a very valuable feature. In cases where there are long distances to the sewer, there are often multiple stations connected serially. If one station fails, it can communicate to the stations behind it to stop pumping and become holding tanks to eliminate the risk of overflow.
The controllers also come with battery packs. The fact that the system can still function when there is a power outage is cost savings waiting to happen. Sometimes extreme heat from the sun will cause a circuit breaker to trip. When that happened with the old system, there was no way to tell. Consequently, people used to check stations two and three times a day. The new system not only works without power, but it also signals when a circuit breaker is turned off; service people know immediately and can fix it before a more serious problem develops.
A value-added feature of the controllers is their ability to protect pump motors from sporadic voltage sags and surges or spikes on the utility line. If a pump is running during one of these events, it can harm the motor.