Editing File:Mini Resetable Trigger Once Plate.PNG

This image shows how to create a resetting pressure plate that will stay triggered until reset.

You also need scaffolding (not shown) to the side, just like you would for an ordinary pump stack and you should forbid the doors when you're done with setup.

You connect the plate at 2 to whatever you want to control (e.g. the drawbridges) and hook your real pressure plate to the hatch using a plate that resets.  The pressure plate at 2 is set to reset triggers whenever depth 1-7 water is on it.  You then connect a lever to the gear up top, which becomes your reset lever, and disengage that gear.  You also have to connect it to a power source (this requires 25 power + whatever you lose in sending power to it).  Lastly, you fill the area marked as 1 with 7/7 water by designating a pond zone.  After you finish, remove the pond zone.

Now, whenever your pressure plate is triggered, it will dump the water from 1 onto the plate at 2, holding that down until you use your reset lever to activate the pump and put the water back on top of the hatch.  Don't forget to turn the pumps off after all the water has moved!

If you have 40 wind power, you can simply put another gear right next to the one shown, then put a windmill above that other gear (because putting a windmill directly on top of the gear shown would cause the windmill to collapse whenever the gear below it was disengaged).  You might also want to build a wall around your windmills to prevent a building destroyer from smashing them.