A line of severe thunderstorms moved through the region on the morning of June 3rd, producing strong lightning and very heavy downpours. At approximately 8:30 a.m., extremely heavy rain hit the park and surrounding community. By 9 a.m., the creek that runs through the park was rising rapidly and preparations for a potential flood were underway. The city of West Branch also activated its flood plan. The creek quickly rose approximately nine feet after about three inches of rain fell on the immediate area. The parkâs maintenance complex was soon flooded. Staff members worked to fill sandbags and created a dike around the shop doorway to keep the water out of the building. Flood water by that time was flowing on the pavement and gravel drives between the buildings and soon came within 20 feet of the Herbert Hoover Presidential Library, which is located on park grounds, threatening to inundate the main transformer boxes for the building. Waters also rose to within feet of several other historic park buildings and filled the visitor center parking lot, closing it to the public for several hours. The main street into West Branch from Interstate 80 is Parkside Drive, which is an NPS-owned road that runs through the park. The flood waters inundated the street, and NPS staff members had to direct traffic so that vehicles could safely navigate the flooded roadway. Similarly, South Second Street, another NPS-owned street for much of its length, was inundated in front of the town police and fire departments and had to be barricaded as a safety precaution. A post-flood assessment showed large areas of bank erosion in the creek, especially in the bends near the Presidential Library. The historic retaining wall suffered erosion damage, and fill near the main support for the southwest corner of the Parkside Drive Bridge eroded away. The visitor center parking lot was completely covered in a layer of mud and debris that had to be cleaned up. The park was back in full operation by 1 p.m. that afternoon.