I contracted a landscaper to install drainage pipes from my downspouts on four corners of my house to the curb in front of my house. Each side is about 60 feet. When I went to test the work by putting running water from a hose in my downspout end of the pipe it took about 5-10 minutes before water came out at the end by the curb. This tells me that water is and will be pooled up in the pipe. Is this okay? It doesn't seem right to me but the contractor says he does this all the time. He used solid corrugated 4 inch black pipe. Shouldn't the water run through the pipe, drain out the front by the curb, and then the pipe should be empty? Should I care if there is standing water in the pipe all the time? I live in Seattle where it doesn't freeze very often so that's not a concern. And the grade is okay, at least enough so water doesn't back up at the downspout and comes out at the curb like it should.

Thanks,
Gary

Drain Pipes

Drain Pipes