I can't figure out how to use Recreation.gov

I will add that we have used it several times, most recently to book 5 days at Sugar Bottom campground on the Iowa River at Iowa City, IA. I knew they had some full hookup sites, and since we were staying longer than a weekend, thought that would be great. But the FU loop shows water/elec, and ONLY after you dive way down into the details of the campsite, does "amenities' show that it does have a sewer hookup. Point is, not always easy to find the "amenities" you want. It can say FU, but only show water/elec. Kind of strange to me. On a positive note, at that campground, just so happens google maps has a full drive thru of every loop....so I could see in a recent pic that indeed, the site we picked has sewer.