1.   After weather reports showed the waterway was covered with thick ice that day, police declined to search the stream.

2.   But doubts about the report surfaced when weather reports showed the waterway was covered in thick ice at the time.

3.   However, doubts about the claim surfaced when weather reports showed the waterway was covered with thick ice at the time.

4.   In several cases, leaking oil covered the waterway, causing it to be shut down to traffic for days.