District 7 of Caltrans has been conducting trials to see whether the use of a single inductive loop to measure vehicle lengths and so identify heavy trucks is feasible. So far, the results have been very promising, according to Lead Transportation Engineer Steve Malkson. Between them, the adjoining ports of Los Angeles and Long Beach, the US's two biggest, cover some 10,700 acres (43km2) and 68 miles (109km) of waterfront.