Water Utility project
Local volunteer opportunity for a senior in Montverde, FL interested in engineering.
Thanks to my experience with both VEX and FIRST, I am able to give back to my community by helping to manage our community water system. I could use some extra help monitoring the system.
When you open the faucet, you expect water to come out.
When you see a hydrant, you expect water to come out.
Did you know that there is a team of technicians, operators and engineers working behind the scenes every minute of the day? Where does the water actually come from?
I have an opportunity for a volunteer to help monitor the recoating of a 15,000 gallons tank and see what the impact is on the community and the systems. The volunteer needs to have access to internet, have a mobile phone for alerts and be willing to learn a lot about water. A tour of the water plant and the community will be provided.
This opportunity includes basic chemistry with monitoring free residual chlorine, physics by understanding the impact of elevation on pressure in the community, math and statistics to predict the number of starts per hour for the motor and lots of sensors hooked up to a monitoring system.
The Recoating of the 15,000 gallons Tank and the electricity bill
The tank inspection in January 2021 confirmed that the community needed to address both the recoating of the 15,000 gallons hydropneumatic tank and reducing the maximum allowable pressure, while improving the fire flow and the potable water pressure to several homes located near Borromini Street and the entrance.
BESH Engineering was hired to propose a solution and RCM Utilties would manage the project and hire any subcontractors needed to implement the solution.
The tank was recoated and the system would finally operate as designed, there was only one issue.
The minimum speed at which the motor could pump up water and not cause cavitation was 54 hz. The electricity usage at this level would increase the daily cost from $5.50 to $77 or more depending on demand.
The issue of electricity usage was brought up by one of the homeowners at the info meeting with Chris Creech. I am not an expert in motors, nor in variable frequency drives so I reached out to my robotics community and published a request for a Leadership Intern. Grant Piersall, a senior at Montverde Academy volunteered to visit the plant and help think through the entire solution and help monitor both the pressure and the electricity usage to see what would be sustainable from an economic point of view. The community needs to be able to afford the solution.
So Grant received a crash course in water treatment plant, and in the monitoring system from Mission Control. Thanks to his passion for programming and previous experience with several robotics programs like SeaPerch, VEX IQ and VEX Robotics Competition, Grant is familiar with wiring sensors and the impact of overheating a motor etc. Not paying attention to a motor overheating can cause you to lose at a robotics competition. We started monitoring the number of starts per hour for the motor. At this time no alarms had been setup and you have to change the graph settings in order to see the information. You can only see the number of starts at the end of an hour. Grant helped monitor the number of starts over several days.
We contacted the manufacturer to see what the motor was rated, ideally we would have an average of 5.5 starts per hour. The water usage in the community and the minimum speed at which the motor has to run did not allow for this to happen, so we researched air pockets with a variable frequency drive.
RCM Utilities added the air pocket and the system balanced out. The motor did not have to run continuously, the pressure to the distribution system is maintained by a combination of the air pocket and the motor. Slowing down the motor was critical.
We discovered that we could see the electricity usage per day and communicated this to the team. All the information is available, you just have to know how to find it.
RCM Utilities and General Utilities have done a tremendous job responding to our concerns based on statistics and data analysis and they verified any suggestions with Rob Ern, the professional engineer overlooking the solution.
I am very grateful to Grant Piersall for being our Leadership Intern and for helping me monitor the water plant, both as volunteers.
For the last 9 days, we have been monitoring the water pressure at the entrance of the distribution system with a mechanical pressure recorder. We learned that the pressure gauge in the monitoring is located next to the well head and not at the tank.
The flow meter blinks when the tank pushes back on the motor. The magnetic flow meter has a propeller that can only rotate in one direction. There is no check valve between the tank and the flow meter, there is one between the flow meter and the well head.
The size of the air pocket is really important. RCM Utilities replaced the sight glass and the probe, turned on the air compressor and now our licensed operator from General Utilities can help monitor the air pocket and alert if the air pocket is not maintained.
Grant and I opened a ticket in Mission Control to add an alarm for the number of starts per hour for the motor.
We are almost finished with the project, we still have a few little things like fixing the sprinkler system, painting the new pipes and adding some gravel so we can clearly see where the ground is etc. But, we are almost at the finish line. We will need to document the operating procedures and the preventive maintenance and schedule the official startup with Rob Ern and we schedule our sanitary survey with the Florida Department of Environmental Protection.
The electricity bill this month will be high, but we know it will be closer to $11 per day moving forward.
Thanks again Grant Piersall for your help volunteering as a leadership intern.
Update: Grant is a mechanical engineering student at Virginia Tech!