RO membranes are rated for maximum pressure OR maximum flux of product water, whichever is reached first.
If the feed water is nearly fresh, very low feed pressure (maybe lower than 100 PSI, 7 Bar) will result in maximum flow of product water. Running like this will not damage the membranes. The "reject rate" of salt removal will be similar, so you will end up with quite pure water.
In the Chesapeake Bay, you will very quickly clog your prefilters, so be ready for that. It is a rich biological soup. If your membranes have been pickled for over 3 years, I would recommend cleaning them before pressurizing to remove as much accumulated biofouling as possible so you do not push it deep into the membrane pores.
Annapolis, MD, USA