Total suspended solids (TSS) include all particles suspended within the water column that will not pass through a filter. They can be both organic and inorganic in nature.  Materials such as soil, algae, decaying organic matter, and particles discharged in wastewater are comprised of both the organic and inorganic portion of TSS. 

In general, TSS particles have an overall negative impact on the aquatic ecosystem.  As levels of TSS increase, a water body begins to lose its ability to support a diverse aquatic ecosystem.  Suspended solids absorb heat and sunlight, which increases water temperature, resulting in decreased dissolved oxygen levels. 

High levels of TSS are very problematic for the Fox River and Bay of Green Bay. Loadings at the mouth of the Fox River for TSS average 132,000 tons/yr. That amounts to approximately 320 tons per day or the equivalent of 24 dump trucks per day.