Signs of Hope. The Detroit River, seen here with the McLouth Steel Corp. looming over it, from being the greatest source of pollution of Lake Erie should be relatively clean by the end of this year. In the last ten years, prodded by Canada and the U.S., the cities and industries around the lake have spent over a billion dollars to clean up their sewage. Even so, the best anyone may be able to do for Lake Erie is to make her happy in her old age.