Declines and extirpations of "E. cinereum", like other aquatic species, are often hard to measure and emerge from compounding factors. Causes are generally human-induced, and include runoff from urbanization, agriculture, mining, and logging. These sources of pollution, among others, are commonly referred to as “nonpoint” sources of pollution, because they are often hard to trace and are difficult to resolve. All of these can lead to substantial siltation, which ultimately destroys their preferred habitat types. Another primary factor in declines are impoundments, such as dams, which have drastically reconfigured river and stream dynamics over the past century.