Third-Generation Installing Company Ohm Excavating Has Become a Father-Daughter Project

Chris Ohm is building the company his father founded into a one-stop shop for onsite treatment services in the scenic lake country of northwest Minnesota

Third-Generation Installing Company Ohm Excavating Has Become a Father-Daughter Project

 Chris Ohm guides an Infiltrator Water Technologies IM-1530 tank into place, while Olivia Ohm is behind the controls of the New Holland backhoe. (Photos by Keri Heibel)

It took some arm-twisting for Grant Ohm to get his son to give up a career in corporate finance and take over his onsite wastewater treatment business.

But since 2018 when he assumed ownership of Ohm Excavating in Audubon, Minnesota, Chris Ohm has expanded and diversified it. The latest addition to the company’s offerings is septic and holding tank pumping, launched last summer.

The company focuses on the Detroit Lakes area, which boasts some 400 lakes within 25 miles. That means often dealing with challenging soils and constricted lakefront properties where fitting a conventional septic system can be difficult to impossible.

Whatever the conditions, customers can count on Ohm Excavating to devise an end-to-end solution. Says Ohm, “We’ll look at your system. We’ll inspect it. We’ll design one, install it, and landscape it at the end if you want us to. If it’s a holding tank system or a regular septic system, we’ll pump it out.” 

Doing business in the scenic Detroit Lakes area has its perks: “Almost every day we have a picnic by the lake, because we’re always working on a lake property.” A big bonus for Ohm is working alongside his youngest daughter, Olivia, who joined the business three years ago and aspires to own it when her father steps away.


Grant Ohm started the business in 1972 after working for a large construction and excavating company based in Fargo, North Dakota, about 40 miles west of Detroit Lakes. “He saw a need,” Chris Ohm recalls. “They were coming out with more and more regulations on septic systems.” He started out working mainly on septics but also digging basements and doing general excavation. 

Chris worked with him summers during high school and for three summers during college at North Dakota State University. He earned an accounting degree and eventually became a certified public accountant and a certified fraud examiner. Corporate life suited him well for more than 30 years.

Meanwhile, his father built a successful business and a solid reputation within the lakes area. “Then in 2015 and 2016 he started pushing for me to buy the business,” Ohm says. “He was getting up there in age, and he wanted to exit. I held back. I wasn’t too sure I wanted to do this. In the corporate life you make pretty good money. 

“Then in 2017 I really got the hard sell. He was either going to sell the business to me or just sell the assets – the equipment, tools and trucks. He didn’t want the name to go to anyone else. I didn’t either, so in late 2017 I made the decision to buy the business from him.”


Ohm Excavating installs in-ground, at-grade and mound treatment systems along with holding tanks. Soil conditions can pose difficulty. “We kind of have both worlds — heavy clay and sand,” says Ohm. South of Detroit Lakes, sand dominates; to the north, clay is more common, and that usually calls for mounds; the company installs 15 to 25 of them per year.

Ohm does soil evaluations using 4-inch augers, one designed for sand and the other for clay. “We try to get down to 84 inches, and then we use the Munsell color charts to see what the soil is doing and make sure it’s good for an in-ground system. If we encounter redox or depleted soils before we hit 84 inches, we don’t keep going. Or if we hit water or any type of limiting condition, we stop.”

Ohm takes pride in giving customers complete information about the site to help them make sound decisions on how to proceed. “We spend a lot of time with customers,” he says. “We walk them through and show them exactly what amount of space they have available, to see if we can fit a system in. We do everything we can to get a standard system into their property.”


That’s sometimes not feasible, especially on lake properties. “One problem is just the sizing of the lots,” says Ohm. “Many lots are only 40 or 50 feet wide. If somebody on one of those lots has a shallow well (less than 50 feet), it becomes challenging to figure out what we can put in. We have to be at least 100 feet away from a shallow well. So if they or their neighbor has a shallow well, it puts them out of luck for getting a system other than a holding tank. 

“The other thing we run into, on smaller lots and even some bigger lots, is the home sizes. The square footage and footprints of the homes are increasing dramatically. Rather than a lake cabin with two or three bedrooms and 1,200 square feet, we’re seeing homes that are 2,500 square feet and have five or six bedrooms. They’re taking up more of the available property, and all of a sudden they get forced into a holding tank system.” 

Permitting for systems is generally straightforward, largely because of the relationships the company has built with county regulators over the years. “They’re each a little different in what they want for the permits,” says Ohm. “Typically we use the Minnesota Pollution Control Agency design sheets to design our systems. We submit all that to the county, and the permits go through pretty easily.”

On jobs, Ohm Excavating usually uses Q4 high-capacity chambers (Infiltrator Water Technologies) for conventional drainfields and washed rock for mounds (with locally sourced washed sand). Septic tanks are precast concrete, or plastic (also Infiltrator) on sandy sites and where ease of handling is an advantage. 

For mound systems, Goulds pumps are the favorite. “I remember as a kid my dad and I would stop in Fargo and pick up Goulds pumps,” says Ohm. “We have pumps out there that have lasted 30-plus years, and they’re still going. There’s a reliability factor we’ve come to trust.” For homes with three or more bedrooms, systems include effluent screens (Polylok). 

Alarms (SJE Rhombus) are installed on the effluent screen and on mound system lift pump tanks: “We give the customer a choice. We typically use the indoor tank alert that has to be wired into the house, but if they want to upgrade they can go to a Wi-Fi alarm.” 


Lake lot owners can be especially protective of their properties, and Ohm Excavating chooses equipment and does work with that in mind. The primary machines are:

  • 2011 New Holland B110B tractor loader backhoe
  • 2009 New Holland L170 skid-steer
  • 2005 New Holland 185B skid-steer
  • Rental mini-excavator

About 65-70% of installations are replacements where systems have failed or the property owner is expanding a home. Customer satisfaction is a key goal. After the initial site visit and discussion of options, team members make return trips as needed to answer questions. 

After the installation, “We make sure we clean up,” Ohm says. “We don’t leave anything behind. We level out the ground so that typically there’s minimal work they have to do. There are a few systems we put in late when the ground is starting to freeze. We can’t clean that up, but we tell the customer we’ll be back in the spring and get it all leveled and looking good.” 

Ohm Excavating has a three-year-old landscaping division that customers can hire for hydroseeding or sodding; the division also plants trees and shrubs and builds retaining walls and patios. 


Pumping was another logical service extension; Chris and Olivia earned their maintainer certifications earlier last year. The company used to contract with others to pump tanks before inspections or replacements but now handles that work in-house while also pumping holding tanks for customers. 

The goal is to become a player in the general tank pumping business. Despite competition from several pumpers in the area, “I feel it’s going to take off faster than we expect,” Ohm says. The company’s first vacuum truck is a 2005 Freightliner with Mercedes-Benz 460 engine, 3,200-gallon steel tank (Centerline), National Vacuum Equipment 866 liquid-cooled pump, heated valves, and two access points for pumping. 

“We tossed around going with a smaller truck so we wouldn’t need a CDL,” says Ohm. “But when we put in holding tanks, typically we install in two 1,500-gallon tanks, so we’re looking at 3,000 gallons to pump out. We figured if we’re going to do this, let’s jump into it.” The tank is about five years old, and the pump is three years old.


Aggressive marketing is a key to building the pumping side, as it has been for the business as a whole. “Before I bought the business it was strictly word of mouth,” says Ohm. “We’ve been in the same location for 40-plus years, and everybody knew my dad. 

“I wanted to build it some more — get a little more of the territory and a little more market share. We have a rotating billboard system, where they go up during our season. We didn’t have a website before I purchased the business; we now get a number of leads through that. We also do Facebook, which Olivia is in charge of. 

“We network with Realtors. If we get a call to do an inspection we’ll ask them to be out there with us. We visit with them and just ask them, if they like what we’re doing, to keep us in mind. We have one realty company in Detroit Lakes where we advertise in the folders they provide when they meet with a prospective client.” The real estate channel started to pick up momentum in 2020, and last year: “We saw it have a huge impact.” 

All in all, Ohm has no regrets about leaving corporate life. “The reward is dealing with the customers and helping them solve a problem,” he says. “I get to be outside. And I get to work with my daughter. I don’t think there’s anything better than that — and just seeing where the future of this business is going. I really haven’t seen a downside. It’s been very rewarding.”


Comments on this site are submitted by users and are not endorsed by nor do they reflect the views or opinions of COLE Publishing, Inc. Comments are moderated before being posted.