A Professional Engineer on every job, that’s the de Jong Excavation difference.

Working in New York’s Adirondack Park and Great Sacandaga Lake regions.

View of a lakeside backyard with trees, a deck, small houses, a dock, a car, and a clear blue sky reflected in the water.

Based in Broadalbin and serving New York State’s Fulton, Montgomery, and Saratoga counties, as well as gateway communities in the Adirondack Park and the Great Sacandaga Lake region, we bring specialized knowledge of seasonal camps, lakefront properties, unique soils, steep lots, tight access sites, and strict environmental considerations.

Built on decades of experience.

A yellow Caterpillar mini excavator digging into the grass in a backyard, with trees and a clear blue sky in the background.

At de Jong Excavation, every project is backed by professional engineering precision from start to finish. Owned and operated by Professional Engineer Mark de Jong, we deliver excavation, system installation, and site development solutions built on accuracy, reliability, and decades of hands-on experience.

Septic Systems are our specialty.

Construction site with a yellow excavator on a dirt mound and a blue pipe installed in a gravel trench surrounded by sand and soil, with trees and power lines in the background.

Partnering seamlessly with our engineering company Makron Engineering PLLC, we handle the entire process from site evaluation and soil testing to design, permitting, and full installation. Whether it’s a new system, a replacement tank or leach field, or a complex lakefront or Adirondack Park project, we deliver engineered solutions built for long-term performance, code compliance, and the unique conditions of each property.

Our Services

Reach out today to schedule your next project!

Give us a call or email your project details to receive an estimate.

  • Could not be happier...

    “We could not be happier with Mark's work. He is a great communicator, he took the time and care to be sure we understood the proposal. He went above and beyond and even solved a longstanding basement drainage mystery savings us thousands down the road. He was on time, did great work and was true to his estimated costs. We will not hesitate to call on him again.” -Nancy

  • We are beyond pleased...

    “We were looking to replace our septic system, we contacted De Jong Excavation LLC/Makron Engineering. Mark who is a Professional Engineer explained, in full detail, the whole process from the design, permit and installation of our septic system. Since we are in an environmentally sensitive area, this was important to us. After this conversation we knew immediately that this was the company we were going with. We also loved the convenience of dealing with one Individual, Mark, who took care of the whole process.


    He arrived as stated and immediately started the mass project. Finishing in a timely manner, landscaping included.
    We are beyond please with his job and confident that he stands by his work.


    You will not regret working with Mark, he's the best. Thank you again for a job well done.” -Bernadette

  • He made sure we were happy with the entire process...

    “Mark went above and beyond with our leaching field replacement project. I couldn't ask for a better company to work on our septic system. Mark was very professional, on time, hardworking and made sure that we were happy with the entire process.” - Amar