Hello! My name is John, and I am a junior environmental science student at the University of Pittsburgh. This past semester, I have been working on an interactive display of the restoration project which reconfigured Nine Mile Run and parts of Frick Park.
I wanted to get involved with Nine Mile Run Watershed Association (NMRWA) because I was inspired by how dedicated and passionate this group is about improving urban water quality. This organization seems to me like part of a greater recommitment by people around Pittsburgh towards restoring our city’s natural beauty.
Conservation has always been important to me, and being an Eastern PA native I grew up enjoying preserved land areas like Stroud Preserve. When I started going to school in Pittsburgh, Frick Park quickly became one of my favorite local spots for mountain biking. Since then I’ve rode over and next to Nine Mile Run countless times, enjoying this oasis of nature in the urban setting.
Clean water has been an interest of mine ever since I moved to Pittsburgh and learned of the challenges urban streams are facing. Also, this past summer I spent much of my time wading in streams while interning for the PA Department of Environmental Protection. These previous experiences blended perfectly in my work with NMRWA, where I could help display innovative solutions to issues of urban stream health.
Using ArcGIS, and past reports on the restoration project, I created maps displaying impervious cover, culvert systems, stream channel reconfiguration, and wetland creation and modification. Along with my maps, the display includes historical photos of the creation of Pittsburgh’s sewer systems from over 85 years ago!
I am grateful to have learned so much about the restoration project in Nine Mile Run, and to be able to learn from leaders in sustainable development. One important takeaway from my experience is that stewardship is never over, and I look forward to continuing to be a part of keeping Nine Mile Run healthy and beautiful!
My ArcGIS story map will be up on the Nine Mile Run website sometime soon, so be on the lookout!
This guest post was written by Rob Rossi, a graduate student in the department of Geology and Environmental Science at the University of Pittsburgh. He was a graduate summer intern of NMRWA in 2015.
Road salt is a common part of winter for many Pittsburgh residents. In Pennsylvania, more than 840,000 tons of road salt (sodium chloride, or table salt) were applied to roadways between 2009 and 2014. Although it helps keep our roads and sidewalks ice and snow free, road salt has unintended consequences. Many people are familiar with the ever annoying winter problems of salt stained clothing or shoes/boots, but the environmental effects of road salt are less obvious. Road salt can have numerous negative effects on the environment, such as increased fresh water and soil salinity, and less obvious effects, such as increased time necessary for rain to soak into the soil. Additionally, when road salt dissolves in highway runoff, these waters have high total dissolved solids (TDS), which can flush roadside soil metals from clay particles (see animated Figure 1). Metals flushed by these reactions can include plant nutrients (e.g., potassium, calcium, magnesium) or toxic trace metals (e.g., arsenic, lead, cadmium).
Road Salt Study in Nine Mile Run
Rob Rossi, a graduate student in the Department of Geology and Environmental Science at the University of Pittsburgh, has been researching the effects of road salt on roadside soils in Nine Mile Run. Specifically, Rob has been analyzing soil and soil water chemistry in samples collected from three roadside soil water sampler “nests”. Each nest is a group of four lysimeters which behave much like giant straws, sucking up soil water samples when a vacuum is applied to the end of the soil water sampler (see Figure 2). The lysimeters collect soil water at roughly 6, 12, 24, and 36 inch depths along a hill slope perpendicular to I-376.
In the soil samples, soil sodium concentrations are highest in soils collected from near the road. Soil sodium concentrations decrease with distance from the roadway, approaching values observed in the local bedrock (see Figure 3). One theory is that high sodium concentrations can be attributed to the minerals breaking down in the bedrock but because sodium concentrations in roadside soils are much higher than sodium concentrations found in the bedrock, minerals in the bedrock breaking down is likely not what inputs sodium to these soils. Instead, the application of road salt to I-376 is likely causing high sodium concentrations in roadside soils.
Sodium concentrations in sampled soil waters peak at different times throughout the year relative to the location along the hillslope (see Figure 4). In particular, the earliest peaks in soil water sodium concentrations occur in the top hillslope soil waters in late February/early March in the intermediate depth (39 and 61 cm depth) soil waters. Additionally, soil water samples from the deepest top hillslope nest have, in general, the highest sodium concentration. While sodium concentrations spike in soil waters collected from all depths of the top hillslope nest station, soil water sodium concentrations peak only in deeper soil waters of the mid hillslope nest. Moreover, the peak in soil water sodium concentrations at the mid hillslope nest do not peak at the same time as when soil water sodium concentrations peak at the top hillslope nest.
These patterns in soil water sodium concentrations suggest that the way soil water flows in roadside soils influences the movement of sodium through these soils. Specifically, because the deeper top hillslope lysimeters (i.e., 12, 24, and 36 inch) peak before the shallowest (i.e., 6 inch) lysimeter, high TDS waters likely interact with deeper soils first. High TDS runoff from the highway is often observed to enter the soil column via infiltration (i.e., water percolating downwards through the soil), which produces a peak in sodium concentrations in the shallowest soil waters first. However, because this pattern in soil water sodium concentrations is not observed in samples collected from the Nine Mile Run transect, sodium is potentially transported to deeper soils via lateral flow originating from leaking highway drains and water flow between bedrock layers.
Previous scientific studies have observed that sodium loadings to soils persist beyond the period when road salt is applied to roadways, and this relationship is also apparent at this study site. Specifically, sodium persists as slow moving wave, where peaks in top hillslope soil water sodium concentrations occur within a month of when road salting ends, and peaks in soil water sodium concentrations at the mid and bottom hillslope stations occur later in the year. Thus, the distance from the roadside affects when soil water sodium concentrations will peak, suggesting that sodium is relatively slowly released from roadside soils throughout the spring and summer.
How does road salt affect the water quality of Nine Mile Run?
The results of this study suggest that sodium and metals are continually flushed to stream waters throughout the year. When sodium levels are high, the ecosystem cannot physiologically maintain a salt balance, which affects aquatic organisms living in the stream – particularly plants and animals that are not adapted to high concentrations of ions, and therefore cannot regulate the water and salt content within their cells. This stress can change the diversity of species within the ecosystem. The increased metal loading could impair the stream ecosystem, negatively impacting aquatic life such as fish. Some metals may be either beneficial or toxic, depending on their concentration. The primary mechanism for toxicity to organisms that live in streams is by absorption or uptake across the gills. The metals that are most toxic to aquatic organisms are Copper, Iron, Cadmium, Zinc, Mercury, and Lead.
Thus, it is likely that road salt application impacts soils down the hillside of I-376, and that the negative impacts of road salt application are not limited to the winter and early spring.
Bright and early on a crisp Sunday morning, Jared Manzo, NMRWA’s GreenLinks Coordinator, guided participants on a tree identification walk through the lower section of Nine Mile Run. With rubber boots required, the first half of the walk traveled in or along the stream itself where no official trail exists.
Several species of trees were highlighted along the stream such as American sycamore, black willow, honey locust, silver maple, boxelder, common hackberry, and hardy catalpa. In a small patch of changing sugar maple, Jared explained what triggers dormancy in trees, the chemicals that produce fall color, and why leaves change color at all with the onset of dormancy.
Before moving back up to the Nine Mile Run Trail, Maranda Nemeth, NMRWA’s Restoration Stewardship Coordinator, took a moment to discuss a project along the run to allow fish to move further up stream. We returned to our starting point on Commercial Avenue by jumping onto the Nine Mile Run Trail. Some interesting species noted along the trail were staghorn sumac, black birch, sassafras, black gum, and bitternut hickory.
Overall, twenty-one tree species were identified. Tree identification focused on the most recognizable features of a given species to help distinguish it in the future. Leaf arrangement, simple leaves versus compound leaves, and the definition of a twig were discussed as well. Hot apple cider and muffins were great snacks given the chillier than usual October morning.
If you are interested in tree identification, look out for walks in 2016 with NMRWA or Tree Pittsburgh! You can get started yourself by getting a guide such as Tree Finder: A Manual for Identification of Trees by Their Leaves or downloading Virginia Tech Tree ID app for your iPhone or Android device.
On Saturday, September 26th, Nine Mile Run staff held a work day with five Operation Better Block Jr. Green Corps students to cleanup three vacant lots on Oakwood & Batavia Streets in Homewood as part of the Rosedale Runoff Reduction Project (RRRP). The OBB students and staff (Jerome Jackson and Demi Kolke) helped NMR staff remove 33 tires and 12 bags of trash from the lots. The weeds were cut down with brush cutters and taken to Agrecycle to be processed into compost or mulch.
This intersection will be the location of the first RRRP construction project scheduled to start in October to install green stormwater infrastructure (GSI). The purpose for cleaning up the lots was to prevent litter from washing into the nearby storm drains whens it rains and eventually into Nine Mile Run. Hopefully this will lessen the load of future stream sweeps!
The Oakwood-Batavia project is scheduled to begin construction in later October. It will be the first GSI facility to be constructed that will extend into the roadway in the City of Pittsburgh. Nine Mile Run with the help of Ethos Collaborative has been working with the City DPW and PWSA to finalize all design features to meet all codes and ordinances.
Nine Mile Run is also hosting a stream tour for residents of Homewood and East Hills on Thursday, October 15th. For more information about the RRRP, please visit: rosedalerain.com
As you may have seen in our Spring newsletter, since 2013 we have been working with the Pittsburgh Parks Conservancy (PPC) on a grant received from the National Fish and Wildlife Foundation’s Five Star and Urban Waters Restoration Program. One of the goals of our partnership on this grant was to develop a culture of stewardship for the Nine Mile Run watershed by engaging a wide range of ages in citizen science and stewardship activities. One way we approached this was to implement PPC’s Mission Ground Truth (MGT) program at Wilkinsburg Middle School.
MGT is an interdisciplinary ecosystem assessment program mapped to PA state academic standards for 7th and 8th grade students that includes in-class discovery activities as well as a field trip to Frick Park. During the field trip, students get to be ecologists for the day, and have the opportunity to use the same tools and sampling methods that scientists use to evaluate the health of forest and stream ecosystems.
Recently, NMRWA staff worked for two days in Frick Park with Environmental Educators from PPC to help lead the Wilkinsburg Middle School students through the field day programming.
We began each morning by discussing goals for the day, then broke into small groups. During the morning session, the groups each explored a section of the Fern Hollow stream while discussing questions such as “how can ecologists detect and measure pollution in a stream?” and “what benefits do humans and animals get from streams?” Then the students recorded data on physical and chemical water quality characteristics, such as temperature, pH, dissolved oxygen, conductivity, and velocity. Next, we explored the benthic macroinvertebrate populations by carefully overturning rocks and collecting samples using a net. To wrap up, we would discuss how everything tied together by asking questions like “based on the data we collected, is the stream healthy or unhealthy?“and “how does the quality of Fern Hollow affect the health of Nine Mile Run?”
After a break for lunch, the students got to venture into the forest for a deeper look at the complex forest ecology present in Frick Park. We identified different tree and plant species and talked about the various ecosystem services that forests provide to animals, streams, and people. We asked questions like “why is biodiversity important in forests?” and “how is the health of this forest related to the health of Fern Hollow and Nine Mile Run?” Then the students used forestry tools to collect data on the location, size, and type of trees, and we looked for evidence of Asian long-horned beetles. To wrap up, we asked questions similar to the morning session, like “is this section of the forest healthy or unhealthy?”
Over the course of the two days, we had a wonderful & enriching experience working with the students and with the PPC staff. Thank you to Mike, Taiji, Steve, and Chelsea for their expertise & enthusiasm in implementing the MGT programming!