I am not certain that I agree with you. Almost nothing in America is over 300 years old. However, the opposite is true in the Middle East. When I was in Israel (many moons ago) I was discussing archaeology with an Israeli. The Israeli was an amateur archaeologist. He told me that in Israel the remains of civilizations were stacked on top of each other, so a big issue is what do you save, e.g. do you remove the remains of one society to get to an earlier civilization. Since the area has been inhabited for many thousands of years, it is really hard to get excited about anything.
For a people that consider electricity to be a luxury, flooding an old site is just a part of daily living.
Understood, it may be a close call in this instance.
...do you remove the remains of one society to get to an earlier civilization[?]
IMO yes, unless the evidence of the earlier civilization renders it both likely there is nothing below the earlier civilization and it is probable there is little or no new knowledge of value to be gained by the effort. No doubt it is always a balancing act with cost being one of the heavy weights. Obviously any removal or disturbance should be carefully documented and filmed.
For a people that consider electricity to be a luxury... That seems key in this instance.