predator help house design

[farmincity]

I want help. I am considering a pool house/ pen /nest box. If I make a similar pen as below With modification . Its pool will be 4 foot across. There will be NO LEDGE around the pool that is in this photo. I am urban my normal predators are cats and skunks. Would the predator cross the pool area to reach the rear nest box? The plan is to close the pen every night. But in case of emergency and it doesn't get closed would this design offer some protection.

 

[ChickenCanoe]

Raccoons love to swim and will gladly go across the pool.

Raccoons are virtually everywhere in North America and have been introduced to Europe and Asia.
There are many more raccoons per sq. mi. in urban settings than rural.