Comparing Trenching And Blasting For Excavation Projects

by Grace Motley

Two of the most common methods for excavating an area, especially a location with major rock formations, are trenching and blasting. It's a good idea to understand how these two processes compare to each other.


When a project calls for precision, there's a good chance that trenching is the better method. Although many skilled professionals can do fairly precise work with blasting, doing exact work requires extensive planning and placement of explosives. This also limits your ability to make adjustments at a moment's notice. Conversely, trenching allows you to quickly respond to changes without overcommitting. This is especially true if you need to excavate in a very specific spot. If so, then trenching is ideal. Qualified operators can get within inches of matching your specifications.


A major upside to blasting is the ability to apply massive force to rock. If you're stuck with a dense rock formation, trenching can become a fast way to destroy equipment. Notably, a mixed solution may still be better in these circumstances. Blasting will allow you to get the toughest rocks out of the way, and you can still take advantage of the benefits of trenching once you have dealt with the situation.


Applying force suddenly with blasting carries with it a price. Materials can and do go flying. That can become a major issue if your location is near anything sensitive, such as other buildings, unstable ground, people, or property. Blasting also exposes you to heightened liability. Most jurisdictions apply strict liability to explosives work, and that means you'll be liable for the entirety of any insurance claims or lawsuits that might arise from a project going sideways.

Trenching limits safety issues to the immediate work area. It also contains most of the liability issues to the work zone, and that means you can handle liability concerns within your contracts.


For most projects, customers need the excavated space to be finished. This provides clean walls for pouring concrete or compacting earth to provide a base for structures or new ground. Materials from trenching are often reusable, reducing waste and costs. Blasting frequently produces less compact walls, irregular lines, and more waste.


It's difficult to achieve a perfectly flat grade with blasting techniques. Trenching allows you to produce a flat bottom with a grade that meets your specifications. This will typically minimize the amount of measuring and finishing you'll have to do.

Contact a company that offers blasting services for more information.