Partial-flow diesel particulate filter using pressure regulated bypass

A system and method for particulate matter reduction. A diesel particulate filtration system includes an inlet, an outlet, an exhaust path between the inlet and the outlet, a diesel particulate filter positioned in the exhaust path between the inlet and the outlet, and a bypass valve, wherein the diesel particulate filtration system is configured to have a diesel engine operatively coupled to the inlet. The bypass valve being configured to open when a maximum allowable engine backpressure is exceeded. When the bypass valve is closed, exhaust gas including particulate matter passes through the diesel particulate filter. When the bypass valve is open, a portion of the exhaust gas passes through the diesel particulate filter and the remainder of the exhaust gas passes through the bypass valve and at least 40 percent of said particulate matter is removed from said exhaust gas.