courtesy of fairmount water works interpretive center
filter with finesse: freshwater mussel innovations in philadelphia
along the banks of the schuylkill river, a major water source for the city of philadelphia, the country’s first city-owned freshwater mussel hatchery has recently opened in part of a larger effort to revitalize rivers across the delaware and susquehanna river basins.
north america has the highest diversity of freshwater mussels in the world, with almost 300 different species. also known as the “liver of the river,” freshwater mussels filter and protect aquatic ecosystems. despite being able to filter between eight and 15 gallons of water per day, mussels face a myriad of threats including industrial development which affected these populations as factories popped up along the schuylkill river during the industrial revolution.
at its worst, philadelphians said the river did not even resemble water. now, scientists at the fairmount water works (fww) freshwater mussel hatchery are working tirelessly to create a space where visitors can learn firsthand about the life of a freshwater mussel and how cleaner river water depends on one of the most imperiled aquatic animals in north america.
in 2017, the philadelphia water department teamed up with the partnership for the delaware estuary to open the hatchery, which is free to the public, and located within the fww interpretive center. the hatchery was designed and imagined by the academy of natural sciences at drexel university, victoria prizzia of habithéque, inc., and artist stacy levy.
introducing philadelphians to the power of the mussel
the hatchery sits along the schuylkill river, which provides 40% of philadelphians with drinking water, with the other 60% being provided by the delaware river. the location of the hatchery, along with preserving pieces of architecture from the original waterworks building are all intentional. according to stacey heffernan, the environmental education planner, “mussels are the gateway animal to get people to care for the waterways.” the hatchery’s proximity to the schuylkill, one of philadelphia’s most iconic green spaces, places it in a culturally significant and emotionally resonant site for many locals.
in addition to this, the hatchery also runs educational programs for philadelphia youth. four schools from the surrounding area participate in the “mussels in the classroom” program. this provides teachers with their classroom’s own recirculating aquaculture system and some juvenile mussels. with this, students are able to engage first-hand with measuring mussels and monitoring water quality.
the hatchery also runs a “mussels in the field” program located at the audubon discovery center, which provides youth from six nearby school districts with similar hands-on interactions, as well as introduces students to blue-green infrastructure. once a month, the discovery center also hosts “mussel maniacs” where adults can participate in similar field work and connect with other conservation enthusiasts.
rebuilding a population of workhorse filterers
since the hatchery opened in 2017, they have consistently propagated around 10,000 mussels each year. the fww mussel hatchery strays away from what these types of aquatic field stations often aim to do, which is to focus on restoring endangered native populations. instead, the hatchery is working to build up common species that once thrived in the schuylkill prior to industrial development, which could lead in local efforts to purify water sources for philadelphians.
in the wild, mussels have a few main ways of propagating, but scientists in the hatchery lab do these manually. this past year, the hatchery achieved a new personal record of the highest number of successful propagations with 20,000 mussels. so far this year, the hatchery more than doubled their yearly propagation numbers with just two inoculation trials. they also performed their first study to determine the rate at which two species of freshwater mussels could remove pollutants.
looking ahead, the results will be used to determine how mussels can work as a complement to traditional pollution control technologies. with all these new milestones, heffernan says, “we have made a lot of strides in a short period of time.