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Magnolia Lake Shoreline Stabilization Project – Phase II

Final Report

June 30, 2012

Prepared By: Bucks County Conservation District

1456 Ferry Road, Suite 704

Doylestown, PA 18901

Magnolia Lake Shoreline Stabilization Phase II – Final Report Page 1

Acknowledgements

The second phase of the Magnolia Lake Shoreline Stabilization Project was

financed by Growing Greener grant SE090185 provided by the Pennsylvania Department

of Environmental Protection. The views expressed herein are those of the author and do

not necessarily reflect the views of the Department of Environmental Protection.

The District would like to thank the Bucks County Commissioners and the Bucks

County Department of Parks and Recreation for their support of this project. In particular,

the District thanks Mr. Bill Mitchell and Mr. Bob Mercer of the County Park Department

and Silver Lake Nature Center for their cooperation and assistance throughout this

project. In addition, the District would like to thank the Greenbelt Overhaul Alliance of

Levittown (GOAL), specifically Mr. Dale Frazier, for their support including providing

educational forums for the public and assisting with planting and subsequent maintenance

of the shoreline buffer.

Project Summary

This project restored 300 linear feet of shoreline erosion through a combination of

regrading and installation of geogrid systems in two heavily compacted sections of the

southern shoreline of Magnolia Lake, located in Bristol Township, Bucks County. In

addition, BCCD and volunteers established a 9,400 ft2 vegetated shoreline buffer.

Introduction

Background

Magnolia Lake is a 26-acre lake located within the Mill (Otter) Creek watershed

in Bristol Township, Bucks County. The lake, initially a borrows area used during the

construction of the Pennsylvania Turnpike, was created in 1953. The lake and

surrounding land was subsequently purchased by the County of Bucks and is currently

maintained by the Bucks County Department of Parks and Recreation (BCPR). The lake

and surrounding parkland provide visitors with a variety of recreational uses such as

fishing, walking, and picnicking. Magnolia Lake discharges to Silver Lake, the focal

point of Silver Lake County Park, via Mill Creek.


Mill (Otter) Creek is a tributary to the Delaware River. In 2003, a comprehensive

lake and watershed management plan was developed to improve and protect the water

quality of streams and County-owned lakes within the Mill (Otter) Creek watershed

(Aqua-Link, Inc. 2003). In the assessment, both Silver and Magnolia Lakes were

classified as highly eutrophic or hyper-eutrophic. Samples collected from the lakes

showed high amounts of nutrients and algae (phytoplankton), which resulted in poor

water clarity (transparency) throughout the entire study period. In addition, Magnolia

Lake was characterized by very low dissolved oxygen levels, and Silver Lake is

extremely shallow due to heavy siltation. Magnolia Lake and Silver Lake were placed on

the Commonwealth’s 303(d) list of impaired waters in 2010 for aquatic life and

recreational impairments associated with nutrient enrichment and siltation. High levels of

nutrients and sediments to the lakes are attributed to stormwater runoff from urban lands

and streambank erosion and failure. The most significant sources of nonpoint source

pollution to the lakes are Queen Anne’s Creek, a major tributary to Mill Creek, and Mill

Creek.

The assessment recommended a variety of in-lake restoration techniques,

watershed best management practices (BMPs) and institutional practices to be

implemented by vested watershed stakeholders. Of those, addressing the severely eroded

southern shoreline of Magnolia Lake was deemed a high priority as the erosion

contributes high quantities of nutrients and sediments to Magnolia Lake, which in turn

flows into Silver Lake via Mill Creek.

In 2004, Bucks County Conservation District (BCCD) received funding from the

United States Environmental Protection Agency (US EPA) and Pennsylvania Department

of Environmental Protection (PA DEP) through Section 319 (Non Point Source Program)

of the Clean Water Act. The Phase I Project, completed in 2006, was to design plans to

restore this section of the shoreline of Magnolia Lake and draft permit applications to

facilitate the implementation of those plans. In 2009, the District applied for and was

awarded funding in 2010 via the PA DEP Growing Greener grant program to continue on

to Phase II of the project.


Project Objectives

The objective of this second phase of the Magnolia Lake Shoreline Stabilization

Project was to implement the plans developed in the first phase of the project and restore

approximately 325 feet of eroded lake shoreline along the central southern shoreline and

adjacent to the lake outlet. These areas of the shoreline run along Lakeland Avenue and

were severely eroding and unable to support vegetation due to overcompaction of the

soil. Through the implementation of this shoreline stabilization project, BCCD hoped to

reduce the soil compaction and shoreline erosion which contributes to the sediment and

phosphorus load to Magnolia Lake, and ultimately, Silver Lake. In addition, the District

hoped to establish additional native vegetation along the shoreline, promoting infiltration

and providing for filtration and nutrient uptake of stormwater by the plant material.

Project Tasks

Permitting

Although draft permit documents had been prepared in Phase I of the project, the

applications were not filed, pending the receipt of funding to complete the second phase.

Once the grant contract and landowner agreement for Phase II were fully executed,

BCCD initiated the process of applying for a State Programmatic General Permit 3

(SPGP-3) to implement the shoreline restoration. A Pennsylvania Natural Diversity

Inventory (PNDI) search was completed; and as several rare and endangered species

inhabit the general project area, BCCD submitted requests for review of potential impacts

of the proposed project by Pennsylvania Fish & Boat Commission and Pennsylvania

Department of Conservation and Natural Resources. After a few months, BCCD received

‘no anticipated impact letters’ from both state agencies, providing clearance to submit the

SPGP-3 registration materials for review by PA DEP. The permit, plans and other

supporting documentation were filed on October 14, 2010 and BCCD was notified of the

authorization on January 4, 2011.

In addition to the state general permit for streambank/shoreline restoration, the

erosion and sediment control plan was submitted for review by Mr. Rich Krasselt,

Environmental Protection Specialist I of BCCD. The plan was submitted March 18, 2011


and determined adequate on March 28, 2011. Bristol Township was contacted during the

permitting process, but no municipal plan reviews were required.

Contractor Selection

After the SPGP-3 and E&S applications were filed, BCCD prepared a request for

proposals (RFP) packet to solicit contractors who had previously completed similar

projects. Seven firms received the RFP packet which included project information and

photos, notification of a pre-proposal site visit with BCCD, and final proposal submission

deadline. Packets were distributed in mid-March and a pre-proposal site meeting was set

for April 1, 2011. Of the three companies who sent representatives to the site showing,

only two submitted proposals within the deadline for review by BCCD and BCPR. After

careful review, B. Blair Corporation were selected for the project. BCCD notified B.

Blair Corporation that their proposal was accepted on May 26, 2011. BCCD finalized the

contract with B. Blair and received the required bond and insurance information on June

22, 2011.

Construction

In preparation for the construction initially targeted for summer 2011, project

partners Bucks County Parks and Recreation Department/Silver Lake Nature Center,

Friends of Silver Lake, Greenbelt Overhaul Alliance of Levittown (GOAL) completed a

volunteer clean-up of the southern and eastern shoreline of Magnolia Lake on April 30 &

May 1, 2011. Over 4 tons of old tires, household garbage and recyclables were removed

from the construction areas and surrounding lake shoreline.

The shoreline construction was initially targeted for late August/early September

to overlap with the typical seasonal dry weather; however, significant rainfall throughout

the latter half of the summer precluded heavy equipment traffic on the site until early

October. A pre-construction meeting was held with BCCD representatives and B. Blair

Corporation on October 4, 2011, and construction started October 5, 2011. The

construction process lasted for approximately 3 weeks. After installing the turbidity

barrier at ‘Area A,’ tree protection fence, and the construction entrance, earthwork was

started at ‘Area B’ near the lake outlet (refer to Appendix A for site plans). Coir logs and

geotextile fabric were installed along the edge of the shoreline, an existing dead tree with


exposed roots was cleared and grubbed. Then the steep, eroding banks of Area B were

regraded to a more gradual slope and covered with the geotextile fabric. Finally, geoweb

material was installed on top of the fabric, filled with a mixture of native soil and

imported topsoil, and the entire area was seeded and matted.

Construction of ‘Area A’ was delayed at multiple stages. First, there was a delay

in the shipment of a portion of the geoweb material; BCCD requested the portion of the

site not be disturbed until sufficient quantities of the material specified in the plans was

available. In addition, once the materials were in place, another delay was encountered

during the initial scarification and regrading due to unanticipated and extensive quantities

of decomposing organic debris that had deposited along the shoreline. Because the debris

prevented proper anchoring of the geoweb material, the material was removed and taken

to an approved yard waste composting facility. To facilitate anchoring the geoweb and

stabilizing Area A BCCD approved a field change to the plans to install additional coir

logs along the water’s edge. As the delays extended the work into mid-October, rain also

delayed construction, at which times the site was matted for temporary stabilization until

work could be continued. Once the site was fully regraded and geoweb placed, topsoil

was mixed with the stockpiled soil and filled in the geoweb. Final seeding and matting

was completed, and the site was considered fully stabilized on October 24, 2011. Per the

construction plans, two 2 ½ inch caliper maples were installed along the edge of Area B

after a final check of the site on October 31, 2011. When construction was complete,

BCCD requested B. Blair Corp. keep construction fencing up to discourage vandalism of

the site while vegetation was planted and became established.

Buffer Establishment

In July 2011, BCCD contracted with NAM Planning and Design, LLC to assist in

the design of the shoreline buffer. BCCD conducted several meetings on site with NAM

LLC principal, Nancy Minich, and Silver Lake Nature Center director, Bob Mercer to

discuss planting logistics and species selection. Due to delays in construction, the initial

planting scheduled for mid-October was pushed back to October 26 and 29. BCCD had

initially coordinated with a local church youth group to provide a large volunteer force

for planting; however, the group could not accommodate a shift in the schedule from


October 15, when the site was still under construction. BCCD distributed flyers and press

releases, posted information on the District website and local media website and

volunteer information websites and reached out at a local high school. Unfortunately, the

October 29 buffer planting was delayed due to an unforeseen early season snowstorm,

which further challenged volunteer recruitment efforts.

The final weather delay work date was scheduled to coordinate with Silver Lake

Nature Center’s regular volunteer first Saturday events. BCCD hosted a staff workday on

site on November 3, 2011 to prepare the site: installing herbaceous material in the

geoweb areas and using an auger on loan from Heritage Conservancy to pre-drill holes

and streamline the planting effort. On November 5, a total of 16 volunteers from Silver

Lake Nature Center, Delaware Valley College, Bristol Township Youth Aid Program

planted from the edge of Area A east along the southern shoreline and throughout Area

B. GOAL volunteers who were unable to assist on November 5th due to a conflict helped

complete the final portion of the buffer installation on November 9, 2011.

In February 2012, BCCD met with Bucks County Parks and Recreation to discuss

measures of preventing damage by park visitors to the newly installed buffer with the

onset of spring and increased park use. At that time, the potential for adding additional

vegetation we also discussed, as additional funds were available in the budget due to

lower than anticipated construction costs, despite the unforeseen circumstances

encountered and additional materials used. BCCD and BCPR agreed to construct a

landscape timber path to delineate walking areas for anglers and other park visitors to

access the lake through the newly established plantings without trampling them. Another

work date was scheduled to coordinate with another Silver Lake Nature Center workday,

May 5, 2012. The volunteer workday was publicized again through Silver Lake Nature

Center, press releases, email and website postings. Unfortunately, despite these efforts

volunteer turnout was very low. Despite the low number of volunteers, the landscape

timber path was completely installed and 60% of the plants were planted by the end of

the workday. BCCD and GOAL completed the additional planting over the following two

weeks.

Warm and dry weather of the late spring and early summer has highly stressed the

newly establishing buffer. BCCD has been regularly watering with the help of GOAL


volunteers, and utilized some of the remaining available funds from this project to

purchase a water pump to facilitate the watering process to maintain the young plants

through dry periods. Although the purchase of this equipment was not initially included

in the Scope of Work, it will be available to BCCD and for loan to watershed associations

upon request both to maintain the Magnolia Lake buffer and for future riparian buffer

projects as well.

Education and Outreach

For the educational component of this project, BCCD conducted two separate

presentations at the Bristol Township Senior Center that were coordinated by GOAL and

highlighted Magnolia Lake as an example of a current watershed restoration project in

the area. The first presentation on watershed management was on Sept 25, 2011, during

which Magnolia Lake was featured as a project to be completed soon. A follow-up

presentation was conducted on April 25, 2012. In addition, BCCD gave a series of lunch

session presentations on this project and the functions of riparian buffers to students at

Harry S. Truman High School on September 28, 2011. BCCD staff encouraged the

students to participate as a means of completing their community service graduation

requirement. In addition to these efforts, BCCD plans to write a newsletter article

highlighting the completion of the grant project for inclusion in both the southeastern

Pennsylvania conservation district newsletter ‘Conservation & You,’ which reaches an

audience of over 1,000 environmental professionals and partner organizations in the

region, and for the Pennsylvania Lake Management Society newsletter ‘What’s Wet,’

which reaches lake association members and environmental professionals focused on lake

management throughout Pennsylvania.

Conclusions and Recommendations

BCCD encountered several challenges in the completion of the Magnolia Lake

Shoreline Stabilization Phase II project. First, despite several outreach efforts, volunteer

involvement was relatively limited for the planting effort given the population size of the

immediate area. This low turnout is attributed in part to weather and construction delays

which hindered the development of a consistent schedule to plan months ahead for the


planting. In hindsight, all planting could have been delayed to Spring 2012 or BCCD

could have requested an extension on the performance period of the grant to conduct all

planting in Fall 2012 and provide an optimal time for planting that did not risk

overlapping with the construction schedule; however, weather delays could be equally

possible in Fall 2012. In addition to limited community involvement, the dry weather of

the late spring has also contributed to significant mortality of the newly established

buffer. The plants installed in Spring 2012 were particularly impacted by the dry weather,

despite watering and maintenance efforts by BCCD and our partners. We therefore

recommend the partners contribute funds and/or seek additional funding to replace

portions of the buffer affected by the drought and strive to install these plantings in the

autumn.

Despite the challenges and setbacks, Phase II of the Magnolia Lake Shoreline

Stabilization project was successful in stabilizing over 300 feet of overly compacted and

severely eroded shoreline despite several weather-related delays throughout the project.

Although the geoweb material did not lend itself to the installation of woody vegetation;

it provides for a stable area for public access along the shoreline that does not negatively

impact water quality. The geoweb prevents future compaction of those sections of the

shoreline even with significant foot traffic or even vehicular traffic, which allows for turf

grass coverage in areas that had previously been eroding and too compacted to allow any

vegetation establishment. In addition, the lower than anticipated cost of construction

allowed for expansion of the existing hedgerow along the shoreline, widening the

forested buffer zone along approximately 700 feet of shoreline from 15 to 25 feet wide.

As the additional 9,500 square feet of shoreline buffer becomes established it will provide

additional protection against future shoreline erosion, while filtering out nutrients and

sediment from stormwater runoff and shading of the water and enhancing wildlife

habitat.


Appendix A. Construction Plans


Appendix B. Project Photos


Photo 1. View facing east of 'Area B,' near lake outlet July 2010.

Photo 2. View facing north of severe shoreline erosion at 'Area B' July 2010.


Photo 3. View of erosion on central southern shoreline ‘Area A’ July 2010.

Photo 4. GOAL, Heritage Conservancy and BCCD show off filled dumpster from Magnolia Lake

shoreline clean-up Spring 2011.


Photo 5. GOAL volunteers removing trash from staging area near eastern shoreline of Magnolia

Lake.

Photo 6. Staging coir logs before initiation of earth work at 'Area B.'


Photo 7. Installation of geoweb near lake outlet (Area B).

Photo 8. Installation of geoweb at Area B.


Photo 9. Area A just prior to installation of stabilization measures.

Photo 10. Staged geoweb materials prior to installation at Area A.


Photo 11. Installation of geoweb and coir logs at Area A.

Photo 12. Final stabilization at Area A.


Photo 13. Start of initial planting at Area B. Orange paint denotes additional areas for plant

placement and installation.

Photo 14. Plant delivery for first phase of planting in Fall 2011.


Photo 15. BCCD staff Jake Borden and Kent Himelwright help prep the site for volunteers Fall 2011.

Photo 16. Planting volunteers break from work to pose for the camera.


Photo 17. Volunteers install buffer in Fall 2011.

Photo 18. Volunteers work to install additional trees and shrubs in Spring 2012.


Photo 19. Area A and Fall 2011 planting area in late Spring 2012.

Photo 20. Phase 2 planting area in late Spring 2012.

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