Last week, preparation began for the removal of the old system. Several days prior to the old station being removed, we took delivery of the new station. This consisted of two skids. One of which supports the motors, filters and vast majority of the plumbing and the second which is a dedicated skid for the control panel.
Tuesday, September 10th
|Old Shaft Being Pulled|
While the heavy lifting was progressing at the pump house, our diver was in the lake where the intake for the wet well sits. He spent most of the day dredging around the current intake screen in preparation for removal and replacement. Over time, siltation and sediment builds around these screens, even with routine maintenance. That being said, it is important to know that the screen, once installed, will be clear so that the new system is not compromised by pumping this material that builds around the screen as water is drawn into the wet well.
Wednesday, September 11th
With the assistance of a 20 ton crane, both new skids were put in place. Although this sounds somewhat easy, I can assure you that tons of measurements are being made and stress levels are high. The control panel skid was placed first. This was done to ensure that the crane operator did not have to maneuver the second skid over and around it. Remember, the main skid weighs in at over 10,000 pounds and that is before motors and shafts have been secured onto it! As the main skid was "flown in", measurements were being made to ensure that it was set in precisely the correct spot. There are many factors that play into this, so if you have further interest, please feel free to contact us. Once it was determined that we had set the main skid in the proper location, the installation team and crane operator began to fly in shafts and the motors. A certified entity handles and oversees the installation of all components and ensures that things are progressing properly. Due to this being a retrofit, the installation process took most of the day, as electrical adjustments were also being made to connect our new power source to the station.
Thursday, September 12th
Mainline Tie Ins
Since the majority of our mainline was installed last summer, the decision was made to leave the last portion of the work to complete during this part of the project. Several factors were key in making this assessment. At the time the other pipe was going in the ground, there wasn't sufficient enough evidence to support the new station layout. This has a very important bearing on how the new mainline is tied into the pump station. Once the engineering team had built the new station conceptually, our irrigation consulting firm could make the determination on what the pipe layout needed to be to tie into it properly. These tie-ins can take time to install due to the sheer size of pipe that is that close to the water source. The contractor was working to complete around 200 linear feet of pipe, most of which is 16" diameter. Pipe that size requires cumbersome mechanical joints, large amounts of concrete for thrust blocks, and time and patience to get the job complete.
Friday, September 13th
Mainline Tie Ins & Start Up
As the work for the mainline wrapped up, our pump service specialist was on-site to go through our start up checklist and to work through the initial cycle of the new system. This is one of the most important pieces as a new system is energized. Items that are scrutinized range from correct electrical output, correct rotation of the motors, station pressure set points and programming sequences of the motors and drives as this system runs off of two variable frequency drives (VFDs).
It is important to remember that while tons of planning go into construction, programming and implementation of a new pump station, very seldom do things go completely as planned. There is always a degree of "fine tuning" that needs to happen so that the equipment operates the way we intend it to.
While service checks were being performed, our diver was also on-site. His primary focus was getting the intake pipe "jetted" and installing the new intake screen. Jetting is a process by which a hose is run up the pipe via the lake side and high pressure water (3400 psi) is used to remove any siltation or build up that has been drawn into the pipe. Specialized heads on the hose insure that the debris is not forced into the wet well, but drawn back into the lake. A final clean up dredge was done, and the new screen was installed.
With overseed right around the corner and temperatures still well above 100 degrees on a daily basis this project had to maintain schedule. Timely monsoonal rains provided some degree of insurance while all of the pieces were falling into place. Please check back, as we will detail the capabilities and options that have been built into our new station allowing us to not only move more water faster, but in a more effective and sustainable manner.