Hidden Valley is a private earth dam located in Dauphin, Pennsylvania, specifically in Middle Paxton Township. Built in 1931, this recreational structure spans 200 feet in length and stands at a height of 22 feet, with a storage capacity of 14.87 acre-feet. Situated on TR Fishing Creek, it is regulated by the Pennsylvania Department of Environmental Protection and undergoes regular inspections to ensure its safety and functionality.

Despite being primarily used for recreation, Hidden Valley poses a high hazard potential due to its location and design. With a fair condition assessment as of the last inspection in December 2020, the dam remains a critical feature in the area's water resource management. Its significance lies not only in providing recreational opportunities but also in its role in flood control and water storage for the surrounding community.

For water resource and climate enthusiasts, Hidden Valley offers a fascinating glimpse into the intersection of human infrastructure and natural ecosystems. As a man-made structure on a vital waterway, it serves as a reminder of the delicate balance between harnessing water resources for human needs and respecting the environment's inherent resilience and power. Its presence underscores the importance of ongoing monitoring and maintenance to ensure both safety and sustainability in the face of evolving climate patterns and environmental challenges.