Lancaster’s push with green infrastructure is well known in stormwater communities. EPA regulations are the motive behind their efforts. The mandate: Lancaster must remove 750 million gallons of stormwater from their system annually.
To do it they’re deploying a range of site level options. On a walking tour before the Millersville Native Plant Conference in June, the Lancaster County Conservation Council, partners with the city on developing and implementing the green infrastructure plan, showed off a number of stormwater features.
City Councilwoman Janine Sirachi interrupted her morning job to greet the group. She commented that one year into their stormwater program Lancaster is still figuring out the balance of regulatory carrots and sticks to obtain results. When asked about political support for green infrastructure, she said it’s been billed politically as a way to create livable, walkable neighborhoods and to add beauty, yet some Councilmen were filled with disbelief that the City will be able to solve the problem using green infrastructure.
The Wolf Museum rain garden in downtown Lancaster, PA is demonstrates the potential of infiltrating stormwater to the public and it looks fabulous. Designed to manage the “first flush” (1” of rainfall), the garden handles rain from the Wolf property and adjacent homes. The garden takes overflow from two rain barrels that drain 1,500 sq. ft. of roof space (about 937 gallons of water from a 1” storm). The garden, excavated to 20” and filled with a media mix of 40% site topsoil, 40% sand and 20% compost is now a thriving garden amenity for the city. Combined with a dry creek bed, the rain garden and rain barrels capture and infiltrate about 40,000 gallons of water a year.
The Wolf Museum rain garden features native and adapted non-native plants in a sweeping curved border. Plants list: Amsonia hubrichtii; Asclepias incarnata, Aster novae-angliae, Chelone lyonii, Eupatorium dubium, Ilex verticillata Sprite, Liatris spicata, Lobelia silphilitica, Monarda fistulosa Claire Grace, Panicum virgatum Ruby Ribbons, Muehlenbergia capillaris, Solidago sphacelata Golden Fleece, and Tiarella cordifolia. Wasn’t it appropriate that it rained when we were touring!
Rain gardens aren’t the only focus. Lancaster has 26 miles of common alleys owned by residents. Initially permeable pavement was preferred, but in some situations they are using underground trenches with dams that overflow into the city’s CSO. Alley projects are cumbersome: Getting all residents to agree is hard and projects can be snagged by unforeseen circumstances such as historic sewer lines. Green alley projects are designed to capture 1” of rain ideally at a cost under $0.15/gallon. This common alley features permeable pavement and captures about 250,000 gallons of stormwater a year. The result is less local flooding and slower stormwater discharge into Lancaster’s combined sewer.
At this demonstration site (right), permeable pavement, regular pavement, trenches and underground storage will capture runoff for a church parking lot. Churches are a target for stormwater management in Lancaster, with the city underwriting most of the expense.
Make rain barrels look nice like these (below) at the Unitarian Universalist Church on Chestnut Street in downtown Lancaster. Overflow from the rain barrels spills into a street side rain garden.
NewTerrain newsletter August 25, 2015.