Today’s Lesson: Irresistible Force Meets Impervious Object

Part 3 in a Series

By SCOTT TAYLOR
Falls Church Times Staff

Wordsmiths, what do you think: “Impervious surface effectiveness demo project”?  The words just trip off the tongue, don’t they?

This is what Patricia Samora, a professional engineer who recently moved from the City of Falls Church, and her associates titled the City’s 2007 grant proposal to the Virginia Department of Conservation and Recreation.  It is perhaps a title only an engineer, landscape architect, or policy wonk could love but whatever you think about those five words – one adjective leavening four nouns – they worked and brought $93,000 to the City from VADCR.

The City’s entire proposal – the four-page application, the five-page narrative – was one of 73 received in Richmond and among the 37 selected for funding by the Virginia Water Quality Improvement Fund.  Right up front in the application, VADCR wanted to know who else had skin in the game; how much was the City going to bring to the table?  $114,000, thank you very much.  Everything came together to create a real opportunity for water quality improvement except nobody was really sure what came next.  Concepts and good ideas had carried the day but there were no projects both designed and sited.

The grant proposal was for implementing low impact development (LID) strategies.  LID was born of the search for alternatives to traditional storm water best management practices.  The simplest way to think about the concept is to recall all that rain the remnants of Ida brought to northern Virginia last week.  Streams of water flowing off roofs and driveways and down the streets produced nonpoint source pollution – something our fourth graders at TJ understand courtesy of their science curriculum.  With those images firmly in mind, ask yourself this question: how would nature have dealt with all that water before miles of asphalt and hectares of development became obstacles to the water entering the hydrologic regime of our watershed?

“Yes,” says Shirley Street of the City’s Department of Environmental Services.  “We study what nature did before everyone came along and messed it all up.  Our low impact development projects capture, harvest, and slow the water” to keep it from running unchecked and unfiltered into Tripps Run and Four Mile Run.

Street, who has a Masters in Landscape Architecture and is also the arborist who formerly served as the city’s urban forester, retired several years ago but returned part-time to work on the LID projects funded through the grant.  Once grant funding is approved, it is sometimes necessary to siphon-off a portion to pay for consultants and contract work before projects can proceed but Street says that was not the case in this instance.

“A survey and soil tests were the only actions contracted out.  All the rest of the work was done in-house,” Street said.  “The Director of Engineering and Construction, Bill Hicks, and Jason Windstorm, both professional engineers, worked with me to analyze the various projects Patricia and I had together considered with the aim of achieving the greatest phosphorous removal for dollars expended.”  The City’s grant proposal estimated an annual phosphorous reduction of 155 pounds.  In the end, Street developed the various concept designs and Windstorm provided the engineering review and design.

So, how would nature have dealt with all that water Ida dumped on the City?  Prior to the growth that produced the urban landscape we call home today, there would have been almost no “impervious” surfaces throughout the forests and meadows that would one day be transformed into the City of Falls Church.  Some of the water would have gradually evaporated or eventually flowed to the Potomac then on to the Chesapeake, but it would have first been absorbed by plants and spongy matter on the ground with excess water slowly filtering into the soil.  Everywhere there is a house, street, parking lot, or sidewalk there is a lost opportunity for nature to deal with the water as close as possible to where the drops hit the ground.

The rain gardens at TJ, one of City’s seven LID project locations, give nature a second chance.  The first project was designed to eliminate the sea of mud and standing water that greeted students and parents as they entered the school through the South Oak Street entrance after a heavy rainfall.  Storm water from the roof flows through three downspouts and is steered by grass swales into a “ponding” area where evaporation, absorption, and filtering can occur.  By design, the garden processes any standing water within 72 hours to preclude the breeding of mosquitoes.

The four cisterns installed over the summer and painted by local artist Bill Abel were designed and sited to capture 7,000 gallons of rainwater, or the first inch of rain to hit the roof of the school, since downspouts drain into the cisterns.  “By capturing the first inch of rainfall, we take 90% of the pollutants out of the water before any overflow hits the stream,” Street explained.

At the rear of the school there is another project that captures runoff from the parking lot in an area where the turf has been replaced by a new mixture of soil designed to maximize water retention and promote natural evaporation or absorption.  Should this garden reach capacity after recurring heavy downpours, excess water passes directly into a nearby storm drain.

All of this carefully considered environmental stewardship at an elementary school could ultimately be viewed as a missed opportunity without an educational component. Enter Jeanette Stewart of Lands and Waters, a grass roots organization promoting watershed education.   One of the Lands and Waters programs, Happenings in Our Habitats, was introduced in the second article of this series and was the basis of Stewart’s classroom instruction to the fourth grade students.  Stewart and her team are currently working with approximately 20 schools across the D.C. metropolitan area providing watershed education for both students and teachers

On a recent sunny morning, Stewart brought Ms. Bragg’s class outside for the hands-on portion of their science lesson.  Vegetation plays an essential role as water cycles through the environment so the task at hand was placing native plants in the rain gardens and creating a riparian walkway along the side of the school that will be sustained by water released from three of the cisterns.  Assisted by volunteers, the students planted Virginia sweet spire, iron weed, goldenrod, blazing star, and winterberry.   This habitat created by the students will be studied over the years and should also result in attractive landscape features on the school grounds.

The life cycle of native plants and animals was also incorporated into the art on the cisterns.  “Shirley (Street) provided me with pictures of dozens of critters and asked me work them into the paintings,” artist Bill Abel said.  Teachers can focus students on the symbiotic relationship between organisms such as the Pawpaw and the Zebra Swallowtail butterfly through the paintings of their life cycles across the seasons.

Ms. Bragg’s class was also joined for their outdoor lesson by Jeanette O’Connor and Michelle Lewis from Living Classrooms of the National Capital Region.  Lewis conducted an “erosion in a bottle” exercise with the students while O’Connor supervised a student-led digital photography project that will produce a photo CD of the students’ work.  “We’re here to foster a love of being outside and respect for the environment,” O’Connor said.

History has shown there is a link between economic and environmental well-being.  The City of Falls Church and other jurisdictions across Virginia may have difficulty pursuing future opportunities like the one afforded by the 2007 grant from the Virginia Water Quality Improvement Fund.  Reflecting today’s economic environment, the fund’s website states:  “The Virginia General Assembly appropriated no new funds for non-agricultural projects in fiscal years 2008 or 2009.  DCR consequently has no plans for a request for proposals.”

The first article in this series is here.

The second article in this series is here.

An overview of the City’s LID projects is here.

An overview of the TJ Rain Gardens proposal is here.