Deborah Sivas, a professor of environmental law at Stanford Law School, reviewed the court’s opinion and said she doesn’t think it “is one bit helpful for solving the problem.”

Sivas believes the decision could ultimately have far-reaching consequences for cities with combined sewer systems across the country — and potentially those without. It could ultimately also affect agricultural runoff permits, she said.

“All those permits, in my mind, are now in jeopardy because they all have that backstop in there,” she said.