Rutherford Ave. To I−93 I−93 Boston Assembly Square On−Ramp Hazardous Cargo Tunnel Detour Routes Leverett Connector From I−93 All Hazardous Cargo ("HC") and Exit 26 Cargo Tankers are prohibited from the Boston Tunnels (new underground highway system). Hazardous Cargo must exit Interstate 93 North at Exit 18 and Interstate 93 South at Spaulding Exit 26. There are HC trailblazers Rehab through the City of Boston to direct HC off Interstate 93 North Commercial Street and South prior to entering the Tunnels and back on to Interstate 93. Causeway Street Southbound I−93 Boston Hazardous Cargo Tunnel Mass. General Detour Route −Take I−93 Southbound to Exit 26 (Storrow Drive/North Station) −From Exit 26, take right onto Nashua Street inbound (towards TD Banknorth Garden) −From Nashua Street, take left onto Lomasney Way −From Lomasney Way, take left onto Causeway Street −Follow Causeway Street and continue straight onto Commercial Street Purchase Street −Follow Commercial St. and continue straight until Cross St. Atlantic Avenue −At Commercial Street and Cross St., take left onto Surface Rd. southbound −Follow Surface Rd. southbound to Purchase Street −Continue on Purchase Street until it New England Medical Ctr. becomes Surface Rd. again −Continue straight on Surface Rd. −At Surface Rd. and Kneeland Street, proceed south onto I−93 Southbound Northbound I−93 Boston Hazardous Cargo Tunnel Detour Route −Take I−93 Northbound to Exit 18 (Mass. Ave) −From Exit 18 continue north on Frontage Rd. to the intersection of Frontage Rd. and Broadway −Proceed north onto the South Station Kneeland Street on−ramp Features Frontage Road −At end of ramp, proceed straight onto Atlantic Avenue northbound Hospitals −Follow Atlantic Ave. northbound bearing right onto Commercial Street Parks −Follow Commercial Street and continue to North Washington Street Schools −Turn right on North Washington St. over the North Washington St. Bridge Boston Medical Ctr. −Continue straight onto Rutherford Avenue towards Sullivan Square Exit 18 From I−93 −Proceed onto I−93 Northbound Northbound adjacent to the Assembly Square I−93 (Mass Ave) on−ramp in Somerville Southbound Source: www.masspike.com 10/06.