My first question is where would a downspout that enters the ground like this lead to/empty out to?
My next problem is that this spout is partially clogged up in the pipe that's under ground level. When there is a heavy downpour, water will shoot out at the connection between the metal downspout and the black, plastic pipe. I've confirmed the clog is in the pipe as I've taken apart the connection and tested both the pipe and the metal downspout with a hose. Water runs through the downspout just fine. But when I put the hose directly into the pipe, water starts to backup. With that said, my second question is does anyone have recommendations for how I could clear the clog in this pipe that's underground?
Lastly, during the last downpour I noticed water bubbling up from the ground from a green, circular plastic cap that's in the yard on a straight line out from downspout. Looking at it further, the cap reads "NDS" and can be pulled up slightly, where I can look inside and see a large amount of "gunk." This seems to be related to the downspout and/or clog but I'm not certain.