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ratm355
How deep to dig drainage ditch?

I have a low spot my asphalt driveway where water pools. When the ground is frozen in winter the easiest path for it is up and over the bulkhead then down into the basement.
I'm going to cut a trench drain into the asphalt to allow the water to get into the ground. I will back fill the trench with stone.
How deep should i make this trench? This is only an issue when the ground is frozen, so do i need to dig below the frost line?
I'm in Massachusetts, and the frost line seems to be 4 feet.
The soil is very sandy and water is not an issue except for this one spot.
Thanks,
Eric

A. Spruce
Re: How deep to dig drainage ditch?

Putting a trench in your asphalt isn't a good idea. The weight of vehicles driving over the edges of the asphalt, along with moisture under it freezing, will destroy the driveway in short order.

I would recommend regrading the surround area so that water naturally drains away from the driveway AND fill the low spot in the driveway with more asphalt to keep water from being able to pool on the driveway.

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