WILLISTOWN CONSERVATION TRUST

  • Facebook
  • Instagram
  • Twitter
  • YouTube
GIVE
  • About
    • HOW WE WORK
    • WHERE WE WORK
    • DIVERSITY, EQUITY & INCLUSION STATEMENT
    • OUR STAFF AND TRUSTEES
    • OUR NATURE PRESERVES
    • JOBS & INTERNSHIPS
    • FAQs
  • LATEST
    • BLOG
    • PUBLICATIONS
    • IN THE NEWS
    • PHOTOS
  • PROGRAMS
    • BIRD CONSERVATION
    • COMMUNITY FARM
    • EDUCATION
    • LAND PROTECTION
    • STEWARDSHIP
      • TRAILS
    • WATERSHED PROTECTION
  • EVENTS
    • EVENT CALENDAR
    • BARNS & BBQ
    • RUN-A-MUCK
    • WILDFLOWER WEEK
    • PLASTIC FREE JULY
    • RUSHTON NATURE KEEPERS (RNK)
  • Support
    • SPONSOR THE TRUST
      • CORPORATE PARTNERSHIP PROGRAM
    • JOIN THE SYCAMORE SOCIETY
    • LEGACY SOCIETY & PLANNED GIVING
    • CAMPAIGN FOR RUSHTON WOODS PRESERVE
    • WAYS TO GIVE
    • VOLUNTEER
    • OUR SUPPORTERS
  • Rushton Conservation Center
You are here: Home / Uncategorized / Open Space and Water Quality | Lessons Learned from Three Years of Stream Monitoring

Open Space and Water Quality | Lessons Learned from Three Years of Stream Monitoring

April 7, 2022 By Watershed Protection Team

By Anna Willig, Watershed Conservation Associate and Lauren McGrath, Director of Watershed Protection Program

Since 2018, the Watershed Protection Program has monitored 10 sample sites in the headwaters of the Darby, Crum, and Ridley Creeks (see map). Through visits every four weeks, the Watershed Protection Team has learned that the headwaters are negatively impacted by human activity on the surrounding landscape. All of the sample sites surveyed had periods of stressful conditions, harming stream life. Stressors included very warm temperatures in the summer, road salts in the winter, and fertilizers throughout the year. However, sample sites with the most open space in their watersheds had the best water quality, indicating that open space preservation is one of the most effective ways to protect and improve water quality in our area.

Water temperature is a critical factor for understanding water quality within a stream system. In Pennsylvania, water temperatures are evaluated based on how they affect trout, which are sensitive to temperature and will not breed or survive if streams are too warm. Water temperature and oxygen levels are tightly linked; cold water can hold the high concentrations of dissolved oxygen needed to support sensitive species, but as water warms, that amount decreases. Figure 1 shows the required temperatures to be considered a Cold Water Fishery — a stream that supports the survival and reproduction of trout — are exceeded at all sites year-round, indicating that streams are too warm to support breeding trout and similarly sensitive organisms and can even reach the point where conditions are stressful for stocked trout during summer heatwaves. These elevated temperatures limit biodiversity at sample sites; only species that tolerate high temperatures can survive and reproduce.

Figure 1. Water temperature at 10 sample sites in the headwaters of the Darby, Crum, and Ridley Creeks from 2018 through 2021. The lines represent maximum allowable temperatures for a Cold Water Fishery (CWF, solid), a Trout Stocked Fishery (TSF, dotted), and a Warm Water Fishery (WWF, dashed) according to PADEP standards. Sampling was paused from April 2020 through December 2020 due to the COVID-19 pandemic.

In addition to monitoring water temperatures, the Watershed Protection Team also analyzed specific conductivity, which is a general measurement of water quality that provides insight into how disturbance on the landscape impacts a waterway. Increases in conductivity occur when road salts, fertilizers, or other pollutants wash from the landscape into the stream. A common cause of increased conductivity in winter months is salt washing off of impervious surfaces — roads, sidewalks parking lots — into waterways. The more impervious surfaces within a watershed, the more opportunity for these contaminants to wash into the streams and increase conductivity.

The Trust’s ongoing study has found that there is a relationship between conductivity and the amount of impervious surface cover in the surrounding watershed. Sample sites in watersheds with the highest percentage of impervious surfaces tend to have the lowest water quality, as indicated by elevated conductivity, while sample sites in watersheds with more open space are the least impaired. Figure 2 shows the relationship between higher conductivity and the amount of impervious surfaces in the watershed. Developing a better understanding of this relationship is critical, as it helps to identify how we can make smart changes in the way we interact with the land to better support the health of the wetlands, streams, and rivers in our region.

Figure 2. Conductivity and impervious surface cover across 10 sample sites in the headwaters of the Darby, Crum, and Ridley Creeks from 2018 through 2021. Boxplots represent specific conductivity and bars represent the percent impervious surface cover of each catchment by area. For each boxplot, the box represents the middle 50% of values and the median. Dots outside of whiskers show values that can be considered outliers.

What can be done to improve water quality in Darby, Crum, and Ridley Creeks?

Based on three years of data, we believe it is important to reduce water temperature and conductivity in local streams to improve habitat and increase biodiversity. One of the most effective ways to accomplish this goal is by planting native plants along streams in riparian areas, the land that borders waterways. Streamside trees and shrubs provide shade, reducing water temperature and increasing dissolved oxygen. Native plants slow and absorb runoff, limiting the amount of pollutants like nutrients and salts that reach the stream, which reduces conductivity. While large scale plantings are important, you do not need to have acres of property to benefit local streams and rivers! Adding native plants to lawns, fields, and gardens goes a long way to improve water quality, even if you do not live alongside
a stream.

Overall, the best tool for protecting and improving the health of our streams is preserving open space, especially in critical habitats like wetlands and riparian areas. Each covered in pavement and will not need road salt or fertilizer applications. Without impervious surfaces, water can infiltrate into the soil and flow through the ground rather than over it, meaning that when it enters the stream, it is cooler and cleaner than if it had run off from a parking lot or road. As a result, water temperatures and conductivity stay down, making streams more hospitable for all types of life.

Not only does protecting open space keep waterways clean for the organisms they house, it also keeps water clean for water sources, and all three creeks — Darby, Crum, and Ridley Creeks — flow into the Delaware River, which provides drinking water for millions of residents. By protecting open space and water quality in the headwaters, we are ensuring that we do not place the burden of cleaning up our pollution on the downstream communities that drink from these waters.

The research conducted by the Watershed Protection Team is ongoing, and a full report will be available this summer.

Filed Under: Uncategorized

OUR NATURE PRESERVES

Our nature preserves are open to the public 365 days per year from sunrise to sunset, providing natural places that offer peace and respite for all. Willistown Conservation Trust owns and manages three nature preserves in the Willistown area - Ashbridge, Kirkwood and Rushton Woods Preserve. We maintain these lands for the … Learn more about our nature preserves.

Upcoming Events

02 February

Winter Stewardship Volunteer Days | Contact us to Join!

View Detail
09 February

Winter Stewardship Volunteer Days | Contact us to Join!

View Detail
10 February
Rushton Conservation Center

Rejuvenate at Rushton Wellness Retreat

915 Delchester Road, Newtown Square, PA

View Detail
No event found!
Load More

DONATE TODAY!

Invest in Nature! ENGAGE CONNECT SPONSOR LEAVE A LEGACY   If you would like to make a gift of securities, such as stocks, bonds, or mutual fund shares, please contact us at 610-353-2562 for instructions. For more … Donate Today

CONTACT

925 Providence Road
Newtown Square, PA 19073
(610) 353-2562
land@wctrust.org

WHERE WE WORK

The work of the Willistown Conservation Trust is concentrated on 28,000 acres of Willistown Township … read more

JOIN OUR MAILING LIST

FAQs

Copyright © 2023 · WCTRUST.ORG