The Impacts of Climate Change and Greenhouse Gas Emissions on the Delaware River Basin

By: Erin Bennett, Policy Intern, CDRW

Caption from website: Austin Ferdock drinks a beer while floating in floodwater that continues to rise over the submerged Vine Street Expressway, Interstate 676, following a huge storm caused by the remnants of Hurricane Ida on September 2, 2021 in Philadelphia, Pennsylvania

The impacts of climate change are already being seen and felt across the Delaware River Basin. From sea level and temperature rise to saltwater migration and intense storms, the impacts of a changing climate threaten over 13.3 million people who rely on the waters of the Basin. In the wake of recent extreme weather events, such as Superstorm Sandy and Hurricanes Ida and Henri, which have caused irreparable damage and tragic loss - it’s essential that we forge a path forward to reduce the impacts of climate change on our communities and limit the devastation in the future. Together, as a Coalition, we must take action to prioritize climate resiliency projects and advocate for Climate Change policy that will help to protect the Basin’s residents, particularly those residing in the most impacted communities.  

Climate Change as a CDRW Priority

Given the ongoing threats to wildlife and the watershed, the Coalition has decided to include climate change as a priority category in 2022 by incorporating climate change considerations into its technical assistance, support, training, and policy goals. Weaving climate change considerations into our every-day work will help to ensure the communities disproportionately impacted are included in the shaping of the solutions, including state and federal level policies and projects with basin-wide implications. Depending on capacity and support, the Coalition will act through direct advocacy, outreach, and education throughout the region and in Washington, D.C. to support the programs and initiatives working to mitigate the effects of climate change.

Effects of Climate Change

Increased Precipitation

Flooding of the Lehigh and Delaware Rivers at Easton on September 19, 2004- photo by Sue Beyer | lehighvalleylive.com file photo

Average precipitation in the U.S. has increased since the 1990s, along with the frequency and intensity of storms. Within 20 years, nearly 170 U.S. communities will be chronically inundated with flooding. According to Pennsylvania’s 2021 Climate Change Impacts Assessment, flooding is predicted to be the highest-risk hazard Pennsylvania will face because of climate change. The increased storm frequency and intensity will aggravate existing issues such as aging stormwater and wastewater infrastructure.

The antiquated sewer and stormwater systems in urban areas throughout the Basin, such as Philadelphia, Camden, Trenton and more, cause the release of untreated sewage into our waterways whenever it rains. Additionally, the high volume of water during a storm can cause flooding and sewage backups in the basements of people’s homes. These infrastructure failings most often affect low-income and black, indigenous, people of color (BIPOC) communities.

In addition to water infrastructure, increased precipitation and extreme weather events are also a threat to transportation infrastructure. For example, according to Delaware’s Climate Change Impact Assessment, many of Delaware’s 48 regulated dams are near or are part of roads and bridges. Washout is a possibility during heavy storms as the dams are vulnerable to damage or failure.

While the intensity of storms will increase, climate change will also affect the frequency of storms. Fewer, more intense winter storms and associated precipitation will cause increased flooding as well as periods of drought. In periods of drought, the decreased snowpack will cause lower flows in the spring. Combined with other climate change impacts, changes in precipitation intensity and frequency will affect our local economies, communities, and natural environments.

Increased in Temperatures

While increased precipitation will have negative effects on communities and wildlife in the Basin, increased air temperature in the form of heat waves will also threaten vulnerable frontline communities as well as wildlife. Earlier migration or altered timing of spawning will negatively affect migratory bird species like the Red Knot by reducing the availability of food and accelerating the decline of the species.

Temperature increases also affect aquatic habitat by diminishing water flows within streams. As temperatures increases, more water will evaporate from our local waterways, making less available for streamflow. This has the potential to not only affect wildlife, but also water supply throughout the Basin, on which residents of New York, Pennsylvania, Delaware, and New Jersey rely upon.

Stream water quality, as well as quantity, will be negatively affected by temperature increases. Turbidity will increase and dissolved oxygen will decrease, affecting aquatic habitats. This will impact local fisheries and local economies dependent on a healthy fishery for tourism.

Graphic: Climate Central

Pennsylvania’s 2021 Climate Change Impacts Assessment predicts the counties within the Commonwealth will continue to get hotter and wetter. The portion of Pennsylvania within the Delaware River Basin will be a part of Pennsylvania that will experience some of the highest temperatures. Particularly, an analysis of 51 years of weather data shows that Philadelphia’s average summer temperature has gotten 3 degrees warmer and average summer nights have warmed by 3.8 degrees. The rising heat temperatures disproportionately affects economically stressed neighborhoods, primarily populated by Black and Latino residents residing in neighborhoods with less trees and more impervious surfaces such as roads, sidewalks and driveways.

Combined with the urban heat island effect, increased temperatures will exacerbate heat-related illness like respiratory and cardiovascular disease.

Saltwater Migration & Sea Level Rise

While communities all throughout the Basin are affected by temperature and precipitation increases, areas along the coast of waterways are particularly vulnerable to the effects of sea level rise. Coastal aquifers are at risk of saltwater intrusion as the ground water table falls below sea-level as sea levels rise. New Jersey’s coastal communities are particularly vulnerable, as “sole source aquifers” provide 50% or more of their drinking water. (Source: DRBC Climate Change Impacts Presentation) Delaware River Basin residents rely on aquifers for drinking water and drinking water intakes along the Delaware River.

Map shows areas in New York’s five boroughs that are projected to face increased flooding over the next 70 years, assuming an increased rate of sea level rise from the past century’s average. As sea level rises, storm surges reach farther inland. Map does not represent precise flood boundaries, but illustrates projected increases in areas flooded under various sea level rise scenarios. (Caption Source: www.globalchange.gov)(Figure source: New York City Panel on Climate Change 2013).

New Jersey is already experiencing sea level rise. Sea levels have risen by 12 inches since 1950 and could rise another inch in the next 5 years. Beach and wetland erosion, along with increasing damages from local storms, puts the State at high risk for major economic and ecological loss. Industry within the Basin is also at risk from sea level rise. The Port of Wilmington and other industrial areas’ facilities in Delaware could be inundated, affecting commerce and industry.  (DE Climate Change Impact Assessment)

According to Observed and Projected Climate Change in New York State: An Overview, New York is vulnerable to sea level rise and it is the most observable effect of climate change in the State. Flooding during high tides, permanent inundation, and more extensive flooding during coastal storms will become reality for New York residents as climate change worsens.

To account for the saltwater migration, there may need to be increased releases from reservoirs and water storage sites. Adding more freshwater from the reservoirs will repel salinity but has implications on the streams downstream from the reservoirs. Both humans and wildlife are dependent on the freshwater releases from the reservoirs, but timing and frequency require a balancing act that meets the needs of humans and wildlife.

Environmental Justice & Climate Change Impacts

Climate change, like many environmental concerns, is an issue of environmental justice. Historically, low-income and black, indigenous, people of color (BIPOC) communities have been disproportionately exposed to environmental pollutants and the negative environmental conditions. In Pennsylvania for example, populations in environmental justice communities constitute less than 1/3 of the Commonwealth’s population, but over 1/2 of the population exposed to highly frequent heat days are members of environmental justice communities.

In the future, city residents will continue to be at risk for negative public health impacts from increased air temperatures combined with the urban heat island effect. Conditions such as asthma are aggravated by poor air quality often seen in the Summer during extremely warm periods. Additionally, the increased energy used to cool homes will put a financial strain on low-income populations.

Other urban issues such as sewer overflows caused by the combination of intense storms and aging infrastructure are felt the most in urban environments. Although different than coastal issues caused by climate change, urban issues such as flooding need to be addressed to ensure communities do not continue to be overburdened with climate change impacts.  

Solutions and Actions to Address Climate Change

While the widespread effects of climate change can seem overwhelming and there is no one solution to address climate change, there are many programs, initiatives, and actions that are or could be implemented on the local, regional, and national scale to comprehensively tackle the issues compounded by climate change in the Basin.  Supporting legislation and programs that aim to address issues aggravated by climate change is one way to advocate for the health of Basin. Some examples include:

  • The U.S. Fish and Wildlife Service’s Delaware River Restoration Program- funds clean water, habitat, recreation, and flow management projects. To date, has funded 123 projects throughout the Basin, totaling $26.6 million.  Funds are administered from the National Fish and Wildlife Foundation through the Delaware Watershed Conservation Fund.

  • Bipartisan Infrastructure Bill- potential for investment in improving/updating stormwater, wastewater, and drinking water infrastructure, as well as nature-based solutions to decrease stormwater. The Bipartisan Infrastructure Bill also includes $26 million in supplemental funds over five years to support the Delaware Watershed Conservation Fund.

  • Build Back Better – the largest effort to combat climate change in American history through investing in clean energy technology, environmental justice, and resiliency solutions.

  • American Rescue Plan – invests in our public-transit systems to decarbonize America’s economy, and invests in water and sewage infrastructure, particularly for tribal governments and Indigenous communities. Additionally, the EPA received ARP funds to support Environmental Justice priorities, particularly health outcome disparities from pollution in vulnerable, frontline communities.

  • NJ’s Cumulative Impacts Legislation - aims to lessen the burden on low-income and Black and Brown communities from pollution-emitting facilities by considering the combined health impacts.

In addition to supporting legislation, Coalition members throughout the Basin are spearheading on-the-ground restoration projects that will help to address the impacts of climate change on our communities. The following projects are funded through the Delaware Watershed Conservation Fund (DWCF) and serve as just two examples from the many projects throughout the watershed addressing climate change.

  • Ducks Unlimited, Inc. received funding in 2021 to restore the hydrology of 150 acres of tidal marsh habitat in the U.S. Fish and Wildlife Service’s tidally restricted Henderson Marsh at John Heinz National Wildlife Refuge. The project will improve marsh function to reduce flooding in local underserved communities, enhance and expand recreational opportunities for kayaking and fishing, and increase public access for environmental education of diverse audiences.

  • The White Clay Watershed Association was a recipient of funds to identify restoration opportunities that mitigate flooding in Avondale Borough, Pennsylvania while also improving water quality and habitat in the White Clay Creek National Wild and Scenic watershed. Project will complete a watershed assessment study and develop a comprehensive restoration plan to inform future restoration projects to benefit an at-risk environmental justice community.

The full DWCF 2021 grant slate can be accessed here.