Your dogs should be able to handle the distance, no problem.
Tara has trained for 4 half marathons with me. I make sure to do a warm up, cool down and stretching with her as well. She usually refuses water on long runs, but I usually offer it every time I take a drink. I don't run her more than ~3 miles if it's over 80 degrees.
Tara NW1 CGC - GSD 2008
Suli - DSH 2006