Loch Sudbury Monster-what if flooding is water table?
Twenty years ago, when putting on an addition, we moved our driveway from one side of the house to the other. It is one of the lowest areas of the yard, but we only had a flooding problem in a wet spring following a severe winter. In anticipation of a problem, we put in a drainage pit (6-8 foot circle with gravel on the bottom) next to a turnaround when the driveway was installed. The end of the turnaround is the lowest part of the driveway, and is lower than the garage.
During those bad winter/spring seasons water would collect in the pit, and also in the adjacent driveway turnaround. During the worst conditions, we would install a pump and hose and pump the water to a culvert on the other side of the yard. Only once did water get into the garage, and never into the house.
This has been happening more frequently the past few years, and this year we have flooding for the first time in the summer. Hauling out the pumps and hoses is getting really old. We believe it may be a water table issue, but it might also be overflow from the pit during a bad rainstorm, which is also spreading mud and debris into the turnaround.
Questions: How do we eliminate flooding if the issue is a water table problem? Can moving the end of the turnaround further from the garage, or raising or lowering the end point help?
Is there a way to get the water into the pit and keep it there, rather than allowing it to flow out of the pit?
Is there a pump that can be installed outdoors?
Finally, our plot plan indicates, with dotted lines, that there may be some piping going across the back yard. The town says it is not part of their system. How can we find out if it exists?
Whom do we contact for help? A contractor? Engineer? Drainage expert? Landscaper? Driveway installer?
BTW, a landscaper suggested running a gravity driven pipe across the backyard, at huge expense. Since we encountered some ledge during our construction, we think this might cost even more than the estimate.