I can attest to the truth of the above statement. To add to the impact, I also have some photos that I took while on my morning commute last Friday, May 1. It was raining and had already rained a lot. The runoff dumped gravel, sand, mud and broken glass directly into the tunnel. The thousands of gallons of runoff were not a problem before the new pipe work. I would recommend having a drain put in that collects the runoff before it goes into the tunnel, because otherwise there will always be mud and water in it.