Building a Comprehensive GI Management Program Through Design, O&M, and Monitoring Plan Development

Many communities across the country have recently started or been actively implementing green infrastructure (GI) programs to improve stormwater resilience and water quality, as well as to comply with regulatory requirements. In 2017, the City of Lancaster entered into a Consent Decree with the U.S. Environmental Protection Agency, the US Department of Justice, and the Pennsylvania Department of Environmental Protection to prepare an amended Long Term Control Plan that included, amongst other items, green infrastructure program plans and manuals– specifically development of a Green Infrastructure Design Manual, Green Infrastructure Operation and Maintenance Plan, and Green Infrastructure Monitoring Plan. The Green Infrastructure Design Manual serves as a technical reference for the design of both public GI installations implemented by the City and private GI installations associated with land development activities and/or stormwater fee credits. The manual provides technical guidance for the planning, design, and construction of individual GI systems by type including bioretention/bioinfiltration (i.e., rain gardens, stormwater planters, stormwater bumpouts), porous pavement, green roofs, subsurface infiltration (including stormwater tree trenches) and detention, cisterns, and naturalized basins. The Green Infrastructure Operations and Maintenance Plan allows the City and private property owners to plan for and conduct effective O&M throughout the useful life of the systems. The Green Infrastructure Monitoring Plan includes GI monitoring methodologies, asset maintenance data schema, programmatic workflows (forms, logs, and procedures), staffing, and record keeping in addition to maintenance tasks (standard maintenance and inspection procedures, maintenance scheduling, and budget requirements). Guidance is geared toward a professional audience (i.e., staff engineers, landscape architects, environmental scientists) but uses charts, tables, and graphics for simplicity and readability. The Green Infrastructure Monitoring Plan was developed in coordination with the City and its GI Performance Evaluation Strategy. The plan includes monitoring planning and development of objectives, site selection and monitoring strategy, preparation of Quality Assurance Project Plans (QAPPs), and preparation of the monitoring plan. In the two years since the development of these guidance manuals, the City has implemented their use for all new and existing green infrastructure projects, standardizing designs and maintenance protocols, including adaptive management strategies, and implementing a comprehensive monitoring program. This includes developing training standards for their staff to perform acceptance testing and performance monitoring for compliance. This following will include detailed examples for each of the three elements of the project, provide guidance on lessons learned from initial GI installations to current revised facilities, and provide a forum for discussion/feedback on best practices for GI design, O&M and monitoring that can help build a comprehensive GI management program.