Congratulations on your decision! Rochester is a wonderful university, extremely well resourced and with excellent faculty. It is frankly comparable to colleges that are more selective.
Rochester is not without access to outdoor activities. Obviously Lake Ontario itself provides all kinds of water opportunities. Both the Genessee River and the Erie Canal with its bike/hike canalway trail running alongside are close to campus. In addition, the Finger Lakes are accessible for water sports. The Genessee River itself runs north out of Pennsylvania’s Allegheny Mountains, eventually emptying into Lake Ontario at Rochester. Along the way, there are 14,000+ acres preserved as Letchworth State Park, also known as the GrandCanyon of the East. Once described as the most beautiful public park in America, the Genessee tumbles through the park over 36 waterfalls, 3 of them 70-100 feet. It’s an hour by car south of campus and is a wonderful place for camping and hiking.
He really didn’t have a bad choice between Rochester and RPI.