How do we learn about our creeks? Scientists & citizens work together to monitor the Tookany Creek Watershed

Julie Slavet
Dec 21, 2016

By Alex Cooper, Community Watershed Specialist

In 2013, a groundbreaking initiative to protect and restore the Delaware River was launched by the William Penn Foundation, which pledged $35 million dollars to dozens of organizations across the Delaware Watershed as part of the Delaware River Watershed Initiative.

The Academy of Natural Sciences leads the science of the initiative. As the leader, they have been collecting water quality data on each watershed since 2012. Their study of the Tookany Creek includes Biological Monitoring, Chemical Monitoring, and Observational monitoring that scores the creek’s ability to support aquatic life.

Academy scientists have been monitoring a site at the bottom of the Tookany Watershed, just before the creek becomes the Tacony at the border of Philadelphia and Montgomery County. This site captures the big picture of the Tookany, where all of the 13 square miles of land that make up the watershed and 21 stream miles of the Tookany Watershed contribute to the water flowing through the site.

You can learn about the Academy’s monitoring findings here.

While our citizen scientists are adults, people of all ages attend Streamkeeper events to learn about and enjoy the creek.













Monitoring at the bottom of the watershed gives us the big picture, but what if we want to know about what’s going on in the smaller tributaries that weave through our neighborhoods?

That’s where TTF citizen scientists, or “Streamkeepers,” come in! They collect data to help us understand the Tookany, Rock, Jenkintown and Burholme Creeks and Mill Run at the top of the watershed where the streams, small enough to step over in most places, run behind homes and schools, under roads, and downhill towards the city.

There are 21 citizen science monitoring sites throughout the watershed, with the goal of collecting data to inform restoration strategies, look for signs of incidents of pollution, and advocate for better protection.

So, what are our citizens monitoring? First, they perform observational monitoring, collecting data on the surrounding land use, the number of trees and leaves in the creek, rate of streambank erosion, and signs of scum, bubbles or oil sheens on the water surface.

Streamkeepers document wildlife and aquatic organisms they see in and around the creek, as well as the amount of algae and presence of aquatic vegetation.

By measuring stream depth and width, then timing how fast it’s moving, Streamkeepers calculate how much water and pollution is carried downstream.
Each month, citizens use test strips to measure Chloride levels at 16 monitoring sites throughout our watershed.














Next, they take water chemistry readings. Each Streamkeeper is armed with a thermometer and test strips for testing chloride, pH, and Nitrate.

Chloride is a naturally occurring ion normally found in creeks at levels around 30 parts per million. It’s also found in road salt as sodium chloride, which you can see liberally spread across our streets over the winter, washing into storm drains and creeks as the snow melts. Streamkeepers have measured levels above 250 parts per million every month in some creeks, which is harmful to aquatic life.

Streamkeepers also test for any extreme changes in pH and Nitrate levels.

Nitrate is often found in the fertilizer that makes your grass lush and green, and pH is the acidity or alkalinity of the water. Nitrate can lead to hypoxic zones, which are areas that have no dissolved oxygen and are therefore dead zones in the creek. Thermal pollution is a major concern in TTF, since many of the trees that provide shade over the creek have been removed and runoff flows off of asphalt that’s been cooking in the sun all day.




The Academy of Natural Science’s chemistry testing reveals that despite our dense development, none of the chemistry parameters they tested were at high enough levels to harm aquatic life. All scientific tests were below EPA’s criteria for freshwater streams. However, the Academy’s biological testing told a different story. Monitoring of macroinvertebrate, fish and algae species indicate poor habitat and water quality conditions. The Tookany Creek suffers from a lack of diversity of species, with the dominant species tolerant of heavy pollution and low-quality waters.

Streamkeepers collect, identify, and release macroinvertebrates like this damselfly (Calopterygidae), which was found in Burholme Creek.










Biological monitoring has some advantages over chemistry. Foremost, biological monitoring shows the long-term impacts to the creek, since these organisms have lived in the creek for their entire lives and we know what type of organisms should be living there. With chemistry, we are only getting a glimpse of one element in the creek at one point in time at one location in the creek.

There are many variables that one water sample could be missing or misrepresenting. For example, after rainstorms the levels measured are often quadruple the levels measured during dry weather, which is when all scientific monitoring was conducted.

These Net-Spinning Caddisfles (hydropsychidae) are commonly found in Tookany Creek.

Entomologists identify the macroinvertebrates collected at the site. Each species of these streambed dwelling bugs have unique habitat and water quality criteria, so the presence or absence of certain species tells us a story about our creek. For example, the stonefly (a fisherman’s favorite) needs nooks and crannies underneath the rocks that form riffles or fast moving, cool water where oxygen can be dissolved within the water. The dirt from our eroded streambanks upstream often settles and becomes embedded in these nooks and crannies, and the lack of tree canopy and warm urban runoff lowers the creek’s capacity to hold oxygen which stoneflies need.

Finger-Net Caddisfly collected in Baeder Creek

Trout have similar habitat needs and love to feast on stoneflies. Unfortunately, neither species is found in the Tookany Creek. Instead we find leeches, aquatic worms and other organisms that can tolerate heavy pollution and lack of habitat. Finding worms or leeches isn’t a bad thing, but when they make up the overwhelming majority of the species identified, this low diversity is a bad sign. The same applies to fish and algae species. The stream is given a score based on the species found, which is known as the Indices of Biological Integrity.

Our Streamkeepers have just begun their own biological monitoring, learning to collect and identify macroinvertebrates found at their monitoring site. They are excited to be acquiring these specialized skills and sharing data that will inform us and our partners at sites all over the watershed, rather than just one location where scientists are performing tests.

In addition to the efforts of our Streamkeepers, TTF conducts a more rigorous assessment of stream health each season, focusing on the stream’s response to our restoration projects. TTF’s monitoring methods during these are identical to Streamkeepers except we also collect water samples to be analyzed by a certified laboratory. Watch for an upcoming blog to learn about this monitoring!

This important citizen science effort is still young and in need of committed residents to help collect enough data to confidently reach conclusions about the health of our waters. We need folks like you, who care about water quality, to help us expand our program.

To become a Streamkeeper today and get started monitoring our streams, contact Alex Cooper at 215-744-1853 or

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