The threat posed by small dams and their short designed life expectancy was demonstrated in dramatic fashion earlier this year. The historic flooding that impacted South Carolina&#x27;s midlands earlier this year was driven by a cascade of dam failures.<p>Everyone saw the pictures of Columbia, SC but that flooding was mostly due to &quot;normal&quot; causes. The city&#x27;s drainage system was overwhelmed by rainfall that exceeded historic levels by several orders of magnitude (higher than even a 1,000 year storm) and the Broad river consequently overflowing its banks. However, that wasn&#x27;t the only place impacted by the storm. South Carolina has an enormous number of small earthen dams, built on private land with the land owner responsible for maintenance.<p>Obviously, these dams were not built to handle such a storm but even if they were, the lack of oversight led to a lack of maintenance, worsening their chances of surviving the initial floods. As upstream dams broke, downstream dams were subjected to massive surges, causing a cascading series of failures, greatly increasing the amount of damage caused by the storm.<p>There are 10,000 to 20,000 unregulated small dams in the state according to the state. They pose an enormous risk as the flooding clearly demonstrated but SC isn&#x27;t alone in sharing this burden.