The backwater levee is designed to keep water from backing into the Yazoo River delta and is designed lower than the mainline levee so that water can flow over it.
Chevron has 100 prospective drilling spots in the Gulf of Mexico, but its highest hopes for a resumption of deepwater drilling lay in an area called the Lower Tertiary Wilcox trend, near where the continental shelf drops off into deep water.
An MTA spokesman said late Monday night that water had reached into all five subway tubes that stretch under the East River between Lower Manhattan and Brooklyn and the Steinway tube between Midtown and Queens.