What is a Mudboil?

The Tully Valley mudboils are volcanolike cones of fine sand and silt that range from several inches to several feet high and from several inches to more than 30 feet in diameter. Active mudboils are dynamic ebb-and-flow features that can erupt and form a large cone in several days, then cease flowing, or they may discharge continuously for several years.

Mudboils have been observed in the Tully Valley in Onondaga County, in central New York State, since the late 1890’s. Mudboils have continuously discharged sediment-laden (turbid) water into nearby Onondaga Creek, which flows to Onondaga Lake. The discharge of sediment causes gradual land-surface subsidence (fig. 1) that, in the past, necessitated rerouting a major petroleum pipeline and a buried telephone cable, and caused two road bridges to collapse. The water discharged from mudboils can be either fresh or brackish (salty).

Mudboil activity was first reported in the Syracuse, NY Post Standard, in a short article dated October 19, 1899:

 

 

 

 

 

First posted August 2009

Original Report FS143-97
Revised Report OFR2009-1173