I'm planning on my first triathlon in September (Savageman) and am wondering if it really is necessary to wear a wetsuit. Swimming is my strength, and I swam competetively in college and in masters, but I've never competed in open water swimming before. The water temperature is supposed to be between 66-70 degrees which I think would be a wonderful temperature to compete in. Any help/suggestions welcome!
You picked a dozy for the first triathlon :)
No, you don't need a wetsuit. The overwhelming reasons why triathletes wear wetsuits are for buoyancy, speed, and compensation for the lack of swim skills, not warmth.
If you are a fish, the challenges that you will face in swimming in an open water race for the first time won't be whether there is a wetsuit on your body. It'll be mostly mental ... adjusting and reacting to people making contact with you (some contacts are more vicious than others), not seeing the bottom, dealing with slower swimmers in front of you, having to sight buoys, etc.
Echoing Tuan. If you're a keen swimmer, nah, you don't NEED a wetsuit. Warmth won't be an issue.
I encourage getting out for some open water swims (OWS) to get familiar/comfortable with that environment. It's very different from the pool. No flip turns, no lines at the bottom.