Infrastructure that supports modern fisheries is increasingly complex. Not only does it include the traditional piers and processors, but major electronics firms and shipyards. There are increasing numbers of vessels that rely on information, advice, and communications that are based on satellite technologies. In coastal communities associated with fishing, the amount and expense of the infrastructure is immense. If fish species change, or their distribution is altered, there can be major impacts.
Available species may change, requiring different vessels, support facilities and processing lines. Alternatively, if the center of distribution of a primary species moves just 10 miles, it is possible that a different city along the coast may be more optimally located. Natural changes in distribution occur all the time, but usually revert back to a "norm". However, if the change begins to look permanent, over time, vessels, crew, and then processors and the support industries, will move to the new location, or they will be at an economic disadvantage to those that do. Ten miles can mean an extra hour to the fishing grounds and an hour back. Eventually, this can lead to a major repositioning of the fleet, its infrastructure, and the families associated with the businesses.
Rising sea level can adversely impact coastal infrastructure, but much of the facilities are replaced every 25-50 years and adjustments can be made. However, in low-lying areas there can be other real problems. Coastal roads may be flooded at high tide, freshwater supplies may become unavailable due to saltwater intrusion into aquifers, and there may be insufficient sewage treatment facilities in areas dependent on septic tanks. Fish processing often requires considerable freshwater. Losses due to saltwater intrusion or due to changes in rainfall patterns would be problematic. Many coastal areas are prone to damage from storms. As sea level increases, waves will be able to reach shore with greater strength and there can be greater damage.