Questions and Answers

University of Georgia

Vidalia Onion and Vegetable Research Center Irrigation System Rebid

# 144482042B

Questions and Answers

Please see the questions and answers that are incorporated into the bid.

1) Approximately how many feet wide are the panels that are planted at the facility for the growth testing purposes that the pivot systems will be watering?

Remove VRI from the bid specs. No variable rate irrigation for this bid.

2) How accurate do you need the VRI system to be? I.E. - How many sprinklers controlled per node that can be turned on/off at any given instant?

Remove VRI from the bid specs. No variable rate irrigation for this bid.

3) Are the existing underground PVC pipelines to be utilized as much as possible or are all new one to be installed? If old ones are to be used, can a drawing of the underground system be provided?

The existing underground pipeline consists of PVC and Transite pipe. A map is attached that shows the existing pipeline.

In your bid, please include a price quote for utilizing all of the existing pipelines as well as a quote for installing all new pipelines.

4) Of the new piping that will have to be installed, what size & rating should it be?

If new piping is installed, it should be 6 inch PVC with a rating adequate to handle the pressure of the irrigation system.

5) What are maximum water requirements for the approximately 58 acres to be watered? I.E. -

How many irrigation inches per week should the pivots and the water source be designed to accommodate?

2.5 inches per 6 days.

6) Variable Rate Irrigation or VRI is a bid requirement; can you specify the type of VRI ( Zone or

Speed}, the number of zones and the maximum size of each zone?

Remove VRI from the bid specs. No variable rate irrigation for this bid.

7) The existing well and pump will deliver up to 2200 gallons per minute, which is way too much for the size of the pivots involved in the bid. Will a smaller pump and motor be added as bid requirements to accommodate the pivots? A water requirement of 450 gallons per minute at

50 PSI at the well head would allow for an application rate of 2.5 inches of water per 144 hour week to be applied to all three pivots.

Yes, smaller pump and motor should be utilized to better match the needs of the system.

8) The existing pump’s soft start panel will run the motor at 1800 rpm which supplies the maximum amount of water and pressure. VRI will allow the customer to regulate the amount of water applied at any given time on each pivot; however, pressure spikes will occur each time a zone is turned off. Will a variable frequency drive starter panel be included in the bid to match the different flow capabilities of each pivot? Also, if the existing motor is changed then the starter panel will need to be changed as well.

Remove VRI from the bid specs. No variable rate irrigation for this bid. However, please include a VFD starter panel in the bid for the irrigation system.

9) Remote pivot control is a requirement. The level of control needs to be addressed. Doyou want full control, the ability to start/ stop the well and each individual pivot remotely? This type of control will require automatic valves at each pivot location. Partial control would still allow the operator to start/ stop the well and pivot remotely; however, each pivot would need a valve to be manually opened for that pivot to apply water.

Full control, the ability to stop and start the well and all pivots remotely.

10) Will you specify that new PVC pipe be installed from the well to feed each pivot? The existing pipe with all the existing taps for the solid set irrigation could be problematic in the future.

The existing underground pipeline consists of PVC and Transite pipe. A map is attached that shows the existing pipeline.

In your bid, please include a price quote for utilizing all of the existing pipelines as well as a quote for installing all new pipelines.

11) Will you allow us to cross the road way entrance with new PVC pipe by cutting and patching the asphalt? Boring under the road would be very expensive.

If necessary to cross the road, the asphalt road can be cut and patched instead of bored.

12) Mechanical stops are listed as a requirement; however, all the pivots are full circle pivots which do not use mechanical stops. Will mechanical stops be removed from the bidding requirements?

Yes, please remove mechanical stops from requirements since they are not necessary.

13) What are the exact pipe size on the existing pipes in the ground?

Please see the attached map. To the best of our knowledge, the main “trunk” line that comes directly from the well is a combination of 12” PVC and Transite pipe that has a 14.5” outer diameter. We dug to the main trunk lines in 2 areas, as indicated on the map. The northern dig/excavation point revealed 12” PVC. The southern dig/excavation point revealed Transite with 14.5” outer diameter. All of the “sub” lines that branch off into each field are believed to be 8” PVC to the best of our knowledge.

14) We need more details on the desired upgrades to the pump station. There are many possibilities for this project and each dealer may chooses a different level of work. Some may choose to do no work at all and continue to “blow off” excess water in low flow situations.

This would result in a lower bid, but not a good quality job. Please provide some guidance regarding:

1. Reuse or replace the existing pump?

Replace existing pump with a smaller pump to better suit the irrigation system to reduce pumping excess water but still meet maximum requirements.

2. Scope of the electrical work to be done?

Any electrical work that is necessary for the updates should be done below or after the existing main disconnect of the incoming 3 phase.

3. VFD or fixed speed/soft start?

VFD

4. Single or dual pump?

Single.

5. Will the discharge manifold be reused or removed/replaced?

If possible reuse the existing discharge manifold.

15) Will any existing pipe that is not used be abandoned in place or must it be removed?

Left in place, does not need to be removed.

16) Will road crossings be cut or bored?

Cut and patched, boring not necessary.

17) Does the university want a full-time pressurized main?

No, only pressurized when irrigating.

18) What kind of valves does the university desire? Automatic controlled by the pivot or manual to isolate machines not in use?

Automatic.

19) More detail regarding the electrical design. Where will the power for each pivot originate? At the pump or will there be a separate drop? If so, where and how many drops will there be?

Power for each pivot will originate at the pump.

20) More detail on what existing pipe is to be reused and what pipe is to be replaced?

The existing underground pipeline consists of PVC and Transite pipe. A map is attached that shows the existing pipeline.

In your bid, please include a price quote for utilizing all of the existing pipelines as well as a quote for installing all new pipelines.

21) More details on the amount of water necessary or available with guidance on minimum application amounts of a specific period of time or a maximum flow rate from the pump details requested above?

The system should be designed with an appropriate smaller pump/motor one that has the capacity to water 2.5 inches of water in 6 days. Flow rates should reflect that.

22) What is the time window for completion of work? Earliest start date and completion deadline?

Work can begin May 1, 2021, and should be completed by July 1, 2021.

23) In Field #2 are we going to get Georgia Power to move existing poles to the edge of the field or across the drive to maximize the Field?

UGA will have GA Power move the power pole out of the field and pay for the cost of this. Do not include costs for this in the bid.