Since the late 19th century, dredging and channelization of the river, as well as the artificial connection to Lake Okeechobee and its use as a water supply for urban and agricultural uses, have substantially altered the hydrology of the river. As a result, both the magnitude and timing of water delivery to the estuary have been substantially altered. Recent programs by the state government have attempted to establish minimum flow levels in the river, in part to help restore the water supply to the Everglades.