(i) Colorado River Basin region, which comprises all basins east of the Santa Ana and San Diego regions draining into the Colorado River, Salton Sea and local sinks from the southerly boundary of the Lahontan region to the California-Mexico boundary.
The regions defined and described in this section shall be as precisely delineated on official maps of the department and include all of the areas within the boundaries of the state.
For purposes of this section the boundaries of the state extend three nautical miles into the Pacific Ocean from the line of mean lower low water marking the seaward limits of inland waters and three nautical miles from the line of mean lower low water on the mainland and each offshore island.
Nothing in this section shall limit the power conferred by this chapter to regulate the disposal of waste into ocean waters beyond the boundaries of the state.