Irvine's road system is one of the best and most sophisticated in the state. It was designed to serve existing residents, businesses and job centers, as well as to expand as the city and surrounding communities grow according to the General Plan. Advance planning and improvements, prior to development, help ensure that minimal traffic impacts occur once a new community opens. Because North Irvine will, over the next three decades, bring more people and cars to the city, a series of traffic improvement strategies will be implemented. The City of Irvine's North Irvine Transportation Mitigation (NITM) Program identifies all measures required to mitigate for traffic impacts resulting from the development of the Northern Sphere, The Great Park, Planning Area 40 and Planning Area 1. In June 2003, the city council adopted a funding program for these transportation improvements. The improvements proposed in the NITM program go beyond the immediate physical boundary of The Irvine Company projects, extending to those planned by the City of Irvine. Specific intersection improvements fully-funded through NITM include Culver Dr. & Trabuco Rd., Culver Dr. & University Dr., Jeffrey Rd & Irvine Center Dr., Alton Pkwy & Irvine Blvd., Jeffrey & Walnut, Sand Canyon & I-5, and more than 25 additional intersections. Among the projects being implemented as part of the Northern Sphere and PA 40 are improvements to Irvine Blvd. between Yale and State Route 133, Sand Canyon Ave. between Interstate 5 and Portola Parkway, Trabuco Road between Jeffrey Road and the 133, and Portola Parkway between Jeffrey Road and State Route 241. Although Culver Drive had been anticipated to extend to the Eastern Transportation Corridor (SR-241), the new plan calls for deleting the extension and terminating Culver at Portola Parkway, at the retail center planned for Planning Area 1. Several factors including recent open space donations, environmental issues and community planning objectives warrant this proposal. While deleting Culver's planned extension to the Eastern Transportation Corridor is now warranted because of dramatic reductions of intensity, it also discourages unnecessary regional traffic from passing through North Irvine.