Sunken Trampoline and Dry Well

Ground-Level Trampoline with Dry Well | 
Eagle, March 2022 

We addressed two problems in this project: drainage from low spots in the back yard and sinking a trampoline to ground level.  Low spots on the north and south end of the lawn caused marshy areas to form whenever it rained.  The customer’s neighbor had brought in fill material to address a similar issue, which only made the problem worse.

The front yard needed to be preserved, so we brought in plywood sheets to protect the sod in the front.  The plan was to completely regrade the back yard to improve water flow, some  toward our planned dry well and some toward the street.

We began by carefully marking the place where the trampoline would go and where drains would be required and removing the yard gate with its adjacent fence panel.  Starting from the south end of the lawn, we used a trenching attachment to cut an 8″ channel for conduit to reach all the way to where the trampoline would be.  Then we laid down approximately 60 feet of flexible conduit into the trench and added a catch basin at the end.

We carefully excavated a circular basin for the trampoline with 2′ tall x 14′ diameter space for a dry well below it.  We then filled the dry well area with drain rock, covered it with geotextile fabric and topped it with pea gravel for a nice finished look.

One hitch in the project was that the customer planned to provide retaining wall material.  However, when the materials arrived, we all agreed that they were inadequate to do the job right.  We discussed solutions, but in the end, the customer elected to manage that part of the project separately.  At the customer’s request, we left a small amount of backfill material so they could finish the project at their convenience.  We left the yard ready for new sod, reinstalled the fence gate, and ensured the client was satisfied with the results!