It depends which NCIS you are referring to. CBS broadcasts NCIS, NCIS: Los Angeles, and NCIS: New Orleans. NCIS is aired on Tuesdays 8/7c. NCIS: Los Angeles is aired on Mondays 10/9 c. NCIS: New Orleans is aired on Tuesdays 9/8c.
Whereas groins are built to change the effects of beach erosion, jetties are built so that a channel to the ocean will stay open for navigation purposes. They are also built to prevent rivermouths and streams from meandering naturally.
These estuaries trap would-be sand before it reaches the coast, Williams explained. As a tie-in, the erosion of beaches especially after major storms often requires beach nourishment, or replenishment projects. Sand is dredged up from offshore and deposited on the shoreline to rebuild lost real estate.