It's very difficult to gauge if an area has a drug "situation". However, the Dover Police Department is considered a superior municipality. Also, the crime rate/100k is far below the national average. There are a lot of college students currently housed in Dover, but all in all, it's become a safe haven. Somersworth and Rochester are a little more dicey, but you should feel pretty secure when situated in Dover.
Please don't hesitate to reach out with any other questions you have about the area or otherwise.
Red Post Realty