CREATE Resilience: Community Resiliency Tour

Hazard: Invasive Species - Japanese Knotweed

Problem Description: Japanese knotweed is a plant introduced from East Asia that is now found in much of the United States and Canada. It spreads quickly in areas that have wet soil at least part of the year through underground rhizomes (interconnected horizontal roots). The leaves and stems of Japanese knotweed form a dense cover over the ground, preventing the growth of native plants. Where Japanese knotweed is found along streams, it can also increase erosion as compared to native streambank vegetation and reduce water quality and aquatic habitat. Japanese knotweed is a challenge to manage because of its rhizomes, which easily split if manual removal is attempted and can still produce new plants from both fragments. Rhizomes can also spread further down streams during floods or through the movement of soil from an area with knotweed. ( https://extension.psu.edu/japanese-knotweed )

Around 2010, areas of Hugh Moore Park in Easton were overgrown with Japanese knotweed, thorny underbrush, and poison ivy. In addition to the ecological issues associated with knotweed, the proliferation of these plants along the bank of the Bushkill Creek and Lehigh River made it difficult for fishermen to access the water and blocked views of the river, and so the City of Easton’s Public Works Department began looking into ways to address the problem.

The Solution: Goats

After initial public pushback to using glyphosate or similar chemicals, which is often the recommended management practice for Japanese knotweed, the Public Works Department and Environmental Advisory Council developed an Integrated Pest Management Program that involved avoiding the use of synthetic chemicals. Members of the Public Works Department attended a panel discussion on herbicides at the Nurture Nature Center where they heard from the owner of Green Goats farm in New York about using goats to control unwanted plants. The city decided to follow up with Green Goats and hired 3 of their animals to eat the Japanese knotweed in Hugh Moore Park.

Goats eat just about any plant they are put into contact with and also trample down the plants in the ground as they move around their enclosure. The 3 goats at Hugh Moore were kept in a solar powered electrified fence that could be moved to different areas of the park as they ate the vegetation. The goats did control some of the knotweed, as well as poison ivy, but to more completely eliminate the large amount of knotweed would likely have required a larger number of goats. The goats also escaped from time to time and had to be brought back with a carrot and a dog leash! This project was a case study in how hazard mitigation can require trying new ideas and tweaking the strategy as it is implemented. Despite those challenges, the project was well received by the public and resulted in helpful lessons about the potential of alternatives to synthetic chemicals in managing invasives.

While the goats are no longer employed by the City, Public Works has continued to investigate creative solutions to the knotweed and is developing a waterfront management plan with the Easton Environmental Advisory Council.

Listen to an interview about this project below.

Hazard: Extreme Temperature

Problem Description: Extreme temperatures pose serious risks to human health. In particular, heat-related illnesses are a leading cause of death from natural weather-related hazards. The implications of extreme heat in urban communities are magnified in areas experiencing what is called the “Urban Heat Island Effect.” Areas with excessive pavement, dark surfaces (like macadam) and limited vegetation can have ambient temperatures significantly higher than nearby rural areas. During heat waves, the urban heat island effect can make evening temperatures especially high, putting residents in these areas at serious risk for heat-related illnesses, including exhaustion, stroke and death. This risk is often compounded when residents are living in older buildings without adequate air conditioning, common in older urban communities in the Northeast. These situations were present in both the City of Easton and the Borough of Wilson, and both communities chose to undertake street tree plantings to reduce temperature, improve air quality, and beautify their neighborhoods.

The Solution: Shade Tree Planting

Easton’s West Ward neighborhood is a highly urbanized area with few green spaces. As in Wilson, several years ago, the City of Easton through its Public Works Department decided to undertake a large shade tree planting initiative to bring trees to this area to help reduce the heat island effect and lower ambient temperatures, while also improving air quality and bringing aesthetic appeal to the streetscape. Working with the Easton Environmental Advisory Council, the city undertook a street tree inventory and developed a list of appropriate street trees. As part of this initiative, in 2019, working with funds from the PA DCNR TreeVitalize program, the City of Easton Forester Robert Christopher, other City staff, and neighborhood homeowners and volunteers planted 52 trees along four city blocks, from 600 to 900 Ferry Street. To calculate the effect of this planting, the City forecasted the benefits these trees would bring, such as carbon sequestration, pollution particulate absorption, greenhouse gas mitigation, stormwater runoff interception, and heating and cooling savings. 

Easton has continued an active street tree planting program throughout its four neighborhoods, planting hundreds of trees and providing education to residents about the proper care and maintenance of trees outside their homes. Partnering with community organizations including Nurture Nature Center, the City has done active outreach to help residents learn about threats to their trees from invasive species, and ways to help keep street trees thriving. 

View a slideshow of the project below.

Hazard: Extreme Temperature

The Solution: Shade Tree Planting

The borough planted 100 trees in one day along Northampton Street, Butler Street and 25th Street sidewalks. Since the initial planting, the borough has continued to expand street tree plantings throughout the borough, and is working with a grant from the Lehigh Valley Greenways program to add street trees and shrubs along the Wilson bike path. In addition to adding much needed vegetation for heat reduction and improved air quality, the annual planting events and enhanced streetscape have brought a sense of neighborhood pride and connectedness– critical elements for resilience.

Watch the video below for an interview and slideshow about this project.

Hazard: Stormwater Runoff

Problem Description: When it rains, the water can be intercepted as it falls (by tree canopy, for example), absorbed into the ground, or run off downhill toward a stream. As development changes the land cover type in many areas, generally toward more paved surfaces and buildings and less forests and green space, the percentage of rainfall that becomes runoff increases because those impervious surfaces don’t absorb as much (or any) water. Increased runoff contributes to flooding, property damage, and water pollution because rainwater collects pollutants from parking lots, roads, and other surfaces and flows quickly to waterways rather than slowly filtering through the ground.

After the remains of Hurricane Ivan came through the Lehigh Valley in September 2004, bringing a large amount of rain over the course of just a few hours, many areas experienced flooding, including a College Hill neighborhood which saw major runoff from Forks Township above. This large volume of water caused overflow of storm drain infrastructure and caused significant damage to streets in the neighborhood. At the time, Sullivan Park was not very widely used and was home to baseball fields that were always wet. This gave rise to the idea for a project to use a portion of the park to construct a stormwater detention wetland.

The Solution: Constructed Stormwater Detention Wetland

Lafayette College and Bushkill Stream Conservancy (BSC) began looking at ways to reduce future risk of damage from stormwater runoff after the 2004 event and decided that Sullivan Park could be a good site to direct some of the water, retain it, and treat it. Dr. David Brandes’s Lafayette College Civil and Environmental Engineering class began testing the site that spring and subsequent classes developed a conceptual plan for the constructed wetland. Lafayette, BSC, the Northampton County Conservation District, and the City of Easton obtained grants from the Pennsylvania Department of Environmental Protection and Department of Conservation and Natural Resources for final design and construction, which involved constructing the necessary structures to divert and retain water. Native plants were added to the wetland and students continued to work to monitor the site and manage invasive plant species. Immediately after construction the wetland just looked like bare dirt with a few weeds, but it has since grown into a forest-like park, home to birds, butterflies, turtles, and other animals. The site also collects rainwater, retains it as sediment settles out, and allows water to slowly infiltrate into the ground or flow out of the wetland.

The Sullivan Park project increases biodiversity, prevents runoff from causing damage to the College Hill neighborhood, and serves as an outdoor laboratory for students learning about wetlands and stormwater management. This project is also a great example of how partnerships - between the college, the stream conservancy, the city, and others - can enhance all participants’ abilities to achieve a community goal.

Special thanks to Professor Dave Brandes for the photographs of this project. 

Hazard: Sinkholes

The problem: As a hazard, sinkholes are uniquely challenging because of the difficulty of predicting their formation. There are no sophisticated warning systems for sinkholes, such as we have for meteorological hazards, like winter storm or flooding. Though sinkholes can often form slowly over time, frequently, the first evidence of the sinkhole is the formation of the hole itself. The Lehigh Valley region is underlain by soluble carbonate rock, a form of karst geology that is prone to dissolve underground as a result of groundwater. As the subsurface rock dissolves, eventually there is not enough support for the land above, and the sinkhole opens. Sinkholes can be small, or very large, dramatic and sudden. A large sinkhole can quickly swallow whatever is in its way, including buildings or vehicles that may be on the land. Sinkholes also present water quality concerns, as the groundwater can absorb contaminants as it moves through the cracks in the rocks. Communities throughout the Lehigh Valley experience sinkholes, and sinkholes frequently rank among the top priority hazards in the Lehigh Valley Hazard Mitigation Plan, which identifies the natural hazard risks facing our region. In urban, suburban and rural communities alike, sinkholes have caused damage to properties, infrastructure including bridges, and personal property.

Solution: Though acute detection is difficult, geologists have produced excellent maps, such as the map below, identifying where the geology of an area makes sinkhole formation more likely. Communities and individuals can use these maps to make themselves aware of the potential for the hazard, and plan accordingly during construction projects and building planning. Homeowners who know their property is in a sinkhole-prone area should purchase a sinkhole insurance policy, which does not come automatically with homeowners’ insurance. A sinkhole insurance policy will help protect you against financial damage if a sinkhole should form on your property. You can contact your insurance company and ask to purchase a rider on your plan to cover sinkhole damage. Communities can help residents by sharing information about the history of sinkholes in the area, and the science about risk for sinkholes. The Federal Emergency Management Agency, following a major sinkhole formation in Harrisburg, PA, now permits communities to use funds from its Pre-Hazard Mitigation Planning program to address sinkhole needs. Communities can also adopt strong sinkhole ordinances that make clear the proper responsibility for sinkhole damage on public and private lands. Because sinkholes can be caused or exacerbated by land uses, such as groundwater pumping and construction processes, communities should continually monitor development in their community to ensure it does not heighten the risk of future sinkhole formation.

Hazard: Stormwater Runoff from Land Development

Problem Description: Densely developed areas in our urban and suburban communities have a much higher percentage of impervious coverage — layers of concrete, asphalt and building materials that don't absorb stormwater. In addition, the manicured lawns and gardens often preferred in developed neighborhoods are not very effective in slowing or holding stormwater. In a rapidly developing area, it is imperative that stormwater is managed so that downstream neighbors aren't flooded by the accumulated water and the pollutants it may carry.

The Solution: Naturalized Stormwater Infiltration and Public Education

Planners and community members thought ahead when planning for the Mill Race housing development in Palmer Township. The establishment of a new park between the proposed housing development and the Bushkill Creek offered an opportunity to provide residents with space for recreation and provide important naturalized areas to manage stormwater and protect the creek. It also provided a unique way to introduce the neighborhood to more sustainable land practices.

This project interfaces the manicured community of the Mill Race development, ball fields, and playgrounds with naturalized landscapes. Natural areas include a constructed wetland storm water filtration pond, riparian areas and meadows. Carefully mowed pathways create a trail throughout the site, bridging high traffic play areas to meadows and woodlands.

The establishment of a meadow, which can take 3-5 years, would require patience and understanding of park visitors. The Bushkill Stream Conservancy developed signage and educational outreach programs in the park to gain acceptance of the project in the adjoining development and in the broader community. Programming taught residents about sustainable landscaping and lawn alternatives, as well as better ways to treat stormwater runoff for the betterment of the Bushkill Creek. Residents were asked to become a "Streamkeeper" by agreeing to implement at least one conservation practice on their own property.

Today, this community park represents a perfect marriage between the manicured and natural, meeting the recreational needs of the neighborhood while providing natural habitat that functions to mitigate the effects of increased storm water runoff.

Hazard: Flooding and Stormwater runoff

Problem Description: Tributaries to the Oughoughton Creek in Lower Bethel Township would occasionally flood and carry cobbles onto roadways and erode fill around culverts causing road collapse. In particular, the Martins Creek/ Belvidere Highway at the intersection of DePues Ferry Road which is the main access to the PPL facilities in Lower Mount Bethel Township, would flood and disrupt transportation. With a changing climate, more heavy rain events are occurring and will continue to occur – together with more development and impervious surfaces, the excess water results in stormwater runoff and localized flooding. To make the area better able to manage stormwater runoff in a sustainable way, Lower Mount Bethel Township, with funding from the Delaware River Joint Toll Bridge Commission and PPL, designed and constructed a Welcome Center that incorporates stormwater management and green building best practices.

The Solution: Stormwater Management, Green Infrastructure (Rain Gardens and Green Roof), Solar Panels

The design of the Lower Mount Bethel Township Welcome Center encompasses multiple strategies for mitigating stormwater runoff, in addition to green building practices (solar panels, energy efficiency, etc.). An array of 14 solar panels located on the roof can create up to 3.15 kilowatts of electricity every hour. The building also has a green roof that captures some stormwater, and pipes surplus water to a stormwater infiltration device. There is a walking path made of permeable macadam that allows water to penetrate the surface and prevents runoff. Grassy swales, planted with native plants, slow the flow of runoff and allow water to absorb into the ground, and are located around the site, as are infiltration trenches that are filled with stones and allow for water infiltration. The nearby Park & Ride lot drains water to various rain gardens, which promotes slow uptake by the surrounding soil and native plants. Overflow is directed to a manmade wetland and permanent pond, allowing all stormwater to be managed on site. Volunteers have helped make the site what it is today – planting native species in the rain gardens and in the green roof – and are always welcome to help with maintenance.