06 Oct FROM IRRIGATION LEADER MAGAZINE: HOW TO RESPOND TO A PUMP STATION LIGHTNING STRIKE
On Saturday, May 30, a major pump station in South Columbia Basin Irrigation District (SCBID) was struck by lightning, disintegrating a bus conductor and knocking out the facility. Within hours, SCBID Manager Dave Solem was on the scene with engineers, electricians, manufacturers, and other relevant personnel. Luckily, the damage to the station was not as bad as feared, and after 2 days of hard work, SCBID had the pump station up and running. In this interview, Mr. Solem gives Irrigation Leader the details of this event and explains how the district reacted.
Irrigation Leader: Please tell us about your background.
Dave Solem: I have been the manager of SCBID since 2010. Prior to that, I managed Klamath Irrigation District for 27 years.
Irrigation Leader: Please tell us about SCBID.
Dave Solem: SCBID is one of the three irrigation districts that make up the Columbia Basin Project (CBP). Our source of water is the Columbia River. SCBID serves about 230,000 of the about 700,000 irrigated acres in the CBP.
Irrigation Leader: What are the main crops grown in your district?
Dave Solem: Alfalfa; wheat; corn; potatoes; beans; grapes for wine and juice; apples, cherries, and other tree fruit; and many seed crops. There are as many as 90 different kinds of crops grown in the CBP.
Irrigation Leader: Tell us about the pump house that was recently struck by lightning.
Dave Solem: We have a pump station in the northern part of our district called the Radar Pump Station. It serves 8,400 acres of farmland in both SCBID and East Columbia Basin Irrigation District. Radar pumps to two primary laterals at a maximum rate of 325 cubic feet per second (cfs). It has five pumps, totaling 8,100 horsepower. It’s a big plant with a high lift that takes power off a 115 kilovolt (kV) Bonneville Power Administration line. A step-down transformer on site brings that power down to 4,160 volts. This medium-voltage pump station is our largest pumping station.
Irrigation Leader: What are the dimensions of the pipe that comes out of the pump plant, and how much water does it move?
Dave Solem: There are two discharges. A 66-inch discharge carries a maximum of 85 cfs up 118 feet. A 72 inch discharge carries a maximum of 240 cfs up 277 feet.
Irrigation Leader: When was this pump plant struck by lightning?
Dave Solem: On Saturday, May 30. We had talked about potential lightning on Friday. It was forecasted to come in late on Saturday afternoon. However, I was awakened by thunder on Saturday at about 5:00 a.m. I got up and looked out the window, and lightning was flashing everywhere in the Tri-Cities.
The sky was a weird color. I knew right then and there that it was going to be a bad day. I got up, got dressed, and waited for the phone call. It only took about an hour. I was kind of surprised that the Radar Pump Station had been hit. It is about 30 miles north of the Tri-Cities, so the storm covered a large area. It actually went even farther north than that, so it probably stretched across 40 miles in total. In any case, I got a call telling me that the pump house had been struck by lightning and that the whole thing was down.
When I arrived, I saw a 5 foot-diameter hole in the building. About half of the 4-inch aluminum bus conductor between the transformer and the inside of the building was gone—it had melted and was splattered on the ground, 20 feet below. Around that time, our electrical supervisor and two of our electricians showed up. I had made a call to Clayton Anderson of RH2 Engineering, who lives in Wenatchee. We had worked with Clayton to rebuild all the electrical components at the station in 2013, and he was familiar with the equipment that had been installed.
He headed over. The fire department was there when I arrived. They were monitoring the scene but hadn’t really tried to do anything, which was probably a good idea. The fuses were out, no power was coming into the station anymore, and it was obvious that it was not going to be operational. Clayton got there around 11:00 a.m. One of the reasons we wanted him there was that he had all the information about the replacement parts we would need.
However, we had learned during the rebuilding of the plant that some of the components took a long time to be manufactured—they weren’t off-the-shelf equipment. Some required 6 months of lead time.
We were extremely concerned about the extent of the damage, because without an operational pumping plant, there would be no water delivered to the land in that area. Time frames of up to a month were going through our heads, and we worried that even that might be optimistic. At that point, we started evaluating the damage. Just after noon, a crew from Eaton, the switchgear and motor control provider, arrived from the Tri-Cities.
They were able to test the station’s large 12,000 kilovoltampere (kVa) transformer. We had just had it serviced and checked in fall 2019, so we had current readings and knew how it had been behaving before the lightning strike. The transformer may have suffered some slight damage, but on the whole, it was okay. We do have a spare transformer on site, but it weighs 82,000 pounds, so moving it would have required a crane and time. We were thankful it was unnecessary.
We knew we were in good shape from the 115 kV line to the transformer. However, the bus work between the low side of the transformer and the switch gear had basically vaporized. We went inside with the crew from Eaton and were able to test the switch gear where the power came in. We could see that the bus was burnt pretty far in, but when we checked the panels and switch gear, we found that those pieces of equipment had not been damaged.
We had spent about a million dollars upgrading the switch gear, the motor control units, and all the wiring for the entire pumping plant. It was just the bus work in the middle that was gone. We like to think that the high-quality surge equipment we put in when we did the upgrades was responsible for this, but maybe it was pure luck. If the lightning had gotten into the switch gear and the motor controls, it would have been a whole different ball game, because those are the long-lead-time items.
We actually had some sections of conductor stored inside the pump station that were intended to be used as jumpers if we ever had to hook up the spare transformer. It just so happened that those six sections of conductor were the right length to tie into the bus on the transformer side, go through the wall, and attach back into the bus bar on the switch gear. We used two cables for each leg and got it hooked up. The lightning hit at 8:00 a.m. on Saturday morning, and we worked through Saturday and Sunday.
We tested it Monday and got the pumps going. They haven’t stopped yet. The farmers were out of water for a couple of days. Now we are in the process of evaluating what it will take to restore the pump station to its original condition.
Irrigation Leader: What will SCBID do to protect against a similar event in the future?
Dave Solem: The plant was designed with bays for four other units. However, because of the way the canals were built, the station was not fitted to the maximum capacity, and those four additional units weren’t installed. The district has talked over the years about installing another unit to supplement the capacity of the pumping plant. The lightning strike made us think about installing a redundant unit that wouldn’t be hooked up at all or would be disconnected from the power source.
In the event of a repeat lightning strike or a similar event that got into the switch gear, there would be an available backup unit and we would be able to deliver at least some water.
Irrigation Leader: How big a unit would that be?
Dave Solem: We’re looking at that right now. We’re evaluating questions like how many acres we could serve at half capacity and so on. SCBID is looking at its data, and RH2 is evaluating the data as well. We’ll look at the design and the cost of putting in another unit or two.
Irrigation Leader: What kind of time frame are you looking at? Are you looking to get this thing resolved over the winter months so that you’re operational next season?
Dave Solem: We are preparing to do the repairs this off-season. We have to go through a request-for-quotation process to be able to make an agreement with RH2. The plan is to prepare a repair contract and bid it in the next few months.
Irrigation Leader: What advice do you have regarding lightning strikes for other irrigation districts that rely on similarly sized pump plants?
Dave Solem: This pumping plant was built in the late 1960s, but our recent upgrades at least gave us a chance of making repairs. In 2013, we replaced the gear, which was obsolete. You don’t want obsolete components in your plants, because if you have an event that causes major damage, you have to start from scratch. Keeping your equipment current and keeping a good inventory of whatever spare parts you can afford—fuses and that type of thing—is important.
Even the conduit on site helped get the plant running sooner. I can’t say that lightning hitting this pump station was high on my list of possible accidents, but it can and did happen. In this case, the pump station lifts water 277 feet, and you can’t easily push water that far with a temporary fix. There weren’t many short-term options. This system serves orchards, grapes, and other high-value crops. Making an investment ahead of time in things like a spare pump, motor, or panel is something the district is going to consider.
Also, it was helpful that we had built relationships with some of our suppliers. One of the members of the volunteer fire department is a contractor who didn’t work on this pumping plant but has worked with us on a different one. He heard about the lightning strike and brought out some conduit for us so that we wouldn’t have to chase it down.
Irrigation Leader: Was this covered by insurance at all?
Dave Solem: We have insurance, but we don’t know what the final damage tally is. The 4 inch bus is original and likely will be highly
expensive to replace. The overhead crane beam took some heat, so we have to get an expert to look at it. The metal siding on this
1968 building is obsolete. We’ve looked all over the country for replacement manufacturers, and the siding replacement estimate
is $20,000. We have a pretty high deductible, so we will be paying a portion of the repairs. If this incident had caused a big crop
failure, it would have been hugely expensive.
Irrigation Leader: Is there anything else that you’d like to add?
Dave Solem: Everybody who was involved—the district electricians and engineers, the watermaster, and assistant watermaster, Clayton Anderson, the guys from Eaton, the Franklin County Fire District No. 4—stepped up and pitched in to solve this problem. It was an amazing team effort—but it is one we don’t want to repeat!
Dave Solem is the general manager of the South Columbia Basin Irrigation District. He can be reached at email@example.com or (509) 547 1735.