A new plan for realigning Hartford’s highways includes removing the current I91-I84 interchange and replacing it with two others, at the northern and southern ends of the city, along with creating a new River Road along the Connecticut River. The interstate highways that were jackhammered through Hartford six decades ago may have increased vehicular mobility, but they did so at great cost to the fabric of the city. Now, a new plan — a mix of previous efforts, along with new ideas — aims to remedy that. Decades ago, the construction of I-91 cut Hartford off from the Connecticut River. I-84 isolated the North End from downtown and consumed a large swath of land and many historic buildings, including the majestic Hartford Public High School campus. The interchange of the two highways laid waste to part of the central business district.