Manhole inserts from The Man Pan are easy to install and provide a short payback. They prevent grit, salt, sand, chemical spills and road oils from entering the collections system. They are effective in stopping surface inflows through exiting manholes. One study showed that just 1/8 inch of standing water on a manhole with concealed pick holes allowed 637 gph of inflow. That can be prevented with a simple manhole insert, gasketed and trimmed to fit the system’s manholes. Most inserts are made of corrosion-resistant plastic and have a neoprene gasket for extra protection. 724/942-9500; www.themanpan.com.