Complex sentence: Barron Creek has been greatly modified for flood control purposes; approximately 67 percent of the total length of creek bed has been hardened, and upstream of El Camino Real the Creek is piped for much of its length.
Split into simpler sentences: Barron Creek has been greatly modified for flood control purposes; approximately 67 percent of the total length of creek bed has been hardened. Upstream of El Camino Real the Creek is piped for much of its length.