Freshwater mussels (unionids) are one of nature’s water filtering mechanisms and a vital component of freshwater ecosystems. Freshwater mussels also serve as a food source for a wide variety of terrestrial and aquatic animal species.
Assessing the impact of road construction projects on adjacent surface waters is a complex task. Environmental impact surveys traditionally assess the presence or absence of individual species, and the potential impact of construction on species present at the construction site. Freshwater mussels are long lived; many freshwater mussel species live more than 40 years. The presence of these long-lived animals does not necessarily reflect the viability of the population. Freshwater mussels may be present, but if their fish hosts have been displaced juvenile and adult stages of mussels, and the various stages of host fish may also be markedly different. Accurate assessment of the impact of road runoff contaminants on mussel populations requires quantification of both adult and juvenile populations.
Various road construction alternatives are available to reduce the movement of rainwater into adjacent streams. Implementation of these construction strategies can add greatly to the cost of road construction. A clear understanding of the actual risk posed by these contaminants in road runoff is needed before suggesting selected site or universal adherence to these construction guidelines.
The main objectives of the research project are:
- To identify the contaminants in road runoff that are entering NC streams;
- To develop non-lethal field sampling techniques for assessing the health of freshwater mussel populations; and
- To measure the potential impact of contaminants in road runoff on mussel health.