I just found small amount of water in the two compartments behind the rear wheel wells, the area in which the 12V battery sits on the passenger side. The bottom / floor is not rusted and is in tact, so it's not sprays from below, but some kind of small leakage. Based on the group's collective experience, are there particular vulnerable spots near those areas that I should check first, to see if they are the source of the leak?
The built-in search feature on PriusChat is functioning again : https://priuschat.com/search/227100436/?q=water+leaks&o=relevance&c[node]=12 There are a bunch of threads that talk about rear hatch related leaks, but the thread below should get you up to speed quickly. Starting reading from post #49, but also view the image at post #121 as I've seen this leak on both sides before. Water leak...into spare tire area etc | Page 3 | PriusChat
SFO's linked post is one of the most common problems on the Gen2 for water leaks. The sealer cracks and water penetrates the seams. Silicone RTV can fix it short term but a proper automotive seam sealer (like 3M "fast" 'n firm") will provide a much more durable repair. You can also have leaks at the tail light gaskets or the mounting holes for the tail gate external trim panels. Searching the forum will turn up all the details. Posted via the PriusChat mobile app.