After conducting research, it appears that the Shore Road 30 boat ramp located in East Haddam, Connecticut, is a public boat ramp managed by the Connecticut Department of Energy and Environmental Protection. The boat ramp is situated on the Connecticut River, providing access to this body of water for boaters.

According to the Connecticut Department of Energy and Environmental Protection's website, the Shore Road 30 boat ramp has a single ramp that is 20 feet wide with a maximum boat length of 20 feet. However, it is important to note that these specifications may be subject to change, so it is advisable to check for any updates directly with the managing authority.

As for the type of craft permitted on the water, the Connecticut River is a navigable waterway that allows for a variety of watercraft, including motorized and non-motorized boats, kayaks, canoes, and paddleboards. However, it is also important to note that certain regulations and restrictions may apply, such as requiring a boating license or specific safety equipment.

In summary, the Shore Road 30 boat ramp located in East Haddam, Connecticut, is a public boat ramp managed by the Connecticut Department of Energy and Environmental Protection. It provides access to the Connecticut River, has a single ramp that is 20 feet wide, and permits a variety of watercraft.