The Original Problem

    The original problem arose from a poorly executed construction project done by the city around 1990. The first picture is the starting point of the problem part of this system. Upstream of this square basin is all concrete pipe and works as it was designed to. There is a 48 inch drain pipe and a 12 inch drain pipe bringing storm water from above the wall and from Buford Highway. There are 2 smaller pipes from springs on each side of the 12 inch pipe. The 48 inch pipe carries the stream from across Buford Highway and runs 24 hours a day. There was a lid on this box with a grate to collect any ground water during a rain.  I will point out that grate in another picture, this open shot shows the pipes into this basin much better.

   This box collects the water from these pipes and routes it to the exit pipe on the wall opposite these pipes. It was at this point the city took over the construction, switching from concrete pipe to corrugated metal pipe. When this box was cast it had the 42 inch metal pipe (shown below) cast in as the exit pipe which should be large enough to move the amount of water this basin receives. Below is a shot of the original basin wall with this metal pipe. It sealed to the wall, wasn't rusted out and worked fine. The real problems started downstream from this 42" pipe as will be explained shortly.

     After this 42 inch metal pipe is where the fun starts. For some unknown reason the city decided to shove a 36 inch metal pipe inside of the 42 inch catch basin exit pipe. This 36 inch metal pipe was used to couple the catch basin at the wall to the 42 inch concrete pipe that was already under Raymond drive. The pipe under the street is located several hundred feet downstream from this basin at the wall. Before this 36 inch pipe was installed there were no flooding problems; although the 36 inch pipe worked all right when it was first installed, it wasn't ideal.  Here is a shot that clearly shows the 36 inch pipe shoved inside the 42 inch one. You can see the 2 layers of pipe (at the bottom of the pipe) once the ground was opened up in this close up shot. This shot is a close up just outside of the catch basin next to the wall.

    The above mentioned catch basin is located between this pipe exit and the base of the wall. The catch basin is about 10-15 feet behind the end of this metal pipe. If there was nothing downstream of this short 42 inch pipe except an open stream bed created with rip rap rocks and plantings, there would be no drain problem with the wall.