Oroville Dam is the tallest dam in the country. It is located in the foothills of the Sierra Nevadas, east of Sacramento, California. All of the recent storms and heavy rains have caused the water in the dam to rise rapidly. Last week, a giant hole appeared in the dam’s main spillway. This caused officials to begin releasing water over the emergency spillway, an occurrence that has never happened since the dam was completed in 1968.
Although the dam itself remains intact, the erosion damage to the spillway increases the risk of failure of the structure. If the dam structure fails, an uncontrollable amount of floodwaters will be released, threatening communities below! At least 188,000 people living downstream were ordered to evacuate in the face of this concern. The dam operators have since been able to start slowing the releases from the dam and residents have since be able to return to their homes. However, the National Weather Service has predicted another atmospheric river to strike the area in the next few days, causing ongoing concerns for the fragile dam and downstream residents.
Further, Lake Oroville is the largest reservoir in the California State Water Project. A network of canals and pumping stations carry water from Northern California to the Central Valley, and even as far as Southern California. If that water is lost, communities state wide will feel its effects.
Repairing the current main spillway could cost between $100 million and $200 million, but that amount continues to rise with the additional erosion damage to the emergency spillway. Along with the failure of the dam near Montello Nevada in the north-eastern part of the state on February 8, 2017, this is just another reminder of how precious and necessary our water resources really are.
