Question

which of the following is a potential consequence of coupling sanitary sewers with storm drains during extreme rainfall events? raw sewage spill over into rivers decreased urban runoff enhanced stormwater treatment

Explanation:

During extreme rainfall, the combined system may exceed capacity. Sanitary sewers carry raw sewage, and if over - flowed due to the coupling with storm drains, raw sewage can spill into rivers. Urban runoff would likely increase rather than decrease as stormwater is added to the system, and there is no enhancement of stormwater treatment since the systems are combined and may lead to overflows.

Answer:

raw sewage spill over into rivers