LEARNING FLOWS FROM NATURE'S CLASSROOM:
SANFORD SCHOOL STREAM AND DAM RESTORATION
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On the grounds of Sanford School is a former pond that was constructed in the 1940s and was used as a storage reservoir for fire protection. The pond was overgrown as a result of upstream urbanization and the masonry dam was substantially degraded. Stream flow was diverting to one side of the dam, resulting in considerable scour of the streambank at and below this location.

Duffield Associates was contacted to design the restoration of the pond and dam. Recognizing the project’s regulatory complexity and opportunity, our engineers and scientists worked with Sanford’s staff to create goals from diverse expectations.

The project goals developed included:

• the partial restoration of the dam and pond;
• to environmentally benefit the stream’s ecology;
• to preserve the aesthetics of the stream valley; and
• to create educational opportunities for the school’s students.

Our firm assisted in obtaining grants to pay three-fourths of the project’s $200,000 cost. The team also coordinated volunteer efforts to install landscaping funded through donations.

Regulators encourage the removal of on-stream dams because of their impact on ecology. Recognizing the project’s historical significance, our approach was to relocate the stream around a scaled down pond, diverting enough water to sustain its health. Our designers used hydrologic modeling and innovative stream restoration methodologies, such as “root wads,” rock cascades, step pools and cross vanes, to ease the stream across the steep site. Multiple techniques were chosen to control flow, create diverse habitat, and provide educational interest. Landscaping was designed to achieve stabilization, aesthetics and habitat creation.

This project, which won the Consulting Engineers Council of Delaware’s Conceptor Award for Engineering Excellence, took an old pond and stream valley which were impacted by urbanization and turned them into a half mile long learning laboratory for Sanford’s students and the surrounding community. The students have the opportunity to observe how man can “help” nature and to measure how the stream’s ecosystems recover and flourish. Since completing the project, student’s scientific observations show the stream’s vital signs are improving. The project’s broader impact will evolve over time, during which the students have a hands-on classroom which teaches the importance of environmental stewardship.