Complex sentence: The Scofield Dam was constructed on the river in 1946, there are plans to build a second dam on the river, upstream on the Scofield Dam, called the Gooseberry Narrows Dam.
Split into simpler sentences: The Scofield Dam was constructed on the river in 1946. There are plans to build a second dam on the river, upstream from the Scofield Dam, called the Gooseberry Narrows Dam.