Dealing with a damp basement

I acquired an older house that had a very damp basement. During wet times or after a rain of an inch or more there was seepage in the basement. The floor drain was well placed and the water drained out but it left the space far too humid to be usable for living or storage. There were no obvious leaks. I did some research and decided to put in a sump pump. That involves breaking out a section of the basement floor, digging a sump pit about 30 inches deep and 30 inches in diameter. The pit is lined with a perforated hard plastic liner that is about 18 inches in diameter. The space around the liner is filled with gravel that will allow the ground water to collect and flow into the sump pit. I dug the pit and went to lunch and upon returning, I found out why the basement floor was nearly always damp. The pit was full of water to the very underside of the concrete floor.
I installed an electric sump pump with a float. When the water gets to a certain depth in the sump pit the pump turns on and the water is pumped outside and away from the house. The sump holds about eight gallons of water and appears to be refilling itself about every fifteen minutes. In just a day and a half, the moisture has stopped seeping up through the floor and by running a dehumidifier in the area it is now usable and livable. Cost of materials: under $200, a lot of sweat and a couple of blisters dramatically improved the space.