Aqueducts may have concrete lined sides which can provide ideal settling substrate. These water conveyances have many associated structures such as moving gates, pumping plants, agricultural turnouts protected by fixed screens and instrumentation in direct contact with the raw water. All these components must be considered vulnerable.
Aqueducts often pass under roadways, rail lines, or other manmade or natural obstacles. The water moves through an inverted siphon and then re-emerges to continue its path. Mussel attachment to the surface of the siphon wall will increase hydraulic friction and reduce the capacity of the siphon. Siphons are difficult and costly to drain for cleaning, so mussel fouling can be a costly impact to these structures.
Gauging stations and float wells are used to track water levels in the various water bodies and the movement of water between the water bodies via aqueducts. Gauging stations usually include a tap line, stilling well and float. The inlet pipe could become colonized with attached mussels and this could impair the accuracy of the gauging station where there are frequent or sudden changes in flow and levels. For locations where flow rates and water levels change very slowly, there may not be a reduction in accuracy as a plugged pipe would still allow water to percolate to the stilling well. The floats could have sufficient mussels attached such that the level readings become unreliable.