Yup my sewage bay is behind the tires.
I lost my entire sewage bay due to a blow out. Valves, bay and part of front of tanks. Looked like a bomb went off inside. :(
Found out the tanks are all 'one molded piece' AND very expensive replacement because it includes the entire molded part that comes to the valves.
I used turnbuckles to bring all the cracked plastic together. And then I screwed heavy wire screening to replace and cover the rest of the damage.
5 years later and all turnbuckles still holding and wire screen still in place.