Southeast Volusia Audubon Society, P.O. Box 46, New Smyrna Beach, FL 32170;

March 2017 Conservation Notes

Conventionally Constructed Parking Lots vs Green Parking lots

One of the most obvious effects of the development of retail and office space along Hwy 44 east and west of I-95 is the clearing of land and the scraping and moving of the soil to place parking lots on a formerly living space.  As usually built, these lots are large fields of concrete and asphalt painted with lines and lit by towers of high-intensity lighting.  This type of “construction-as-usual” has a deleterious effect on the local environment.  As stated in the EPA’s Green Parking Lot Resource Guide (February 2008):

Pavement is an impervious, heat absorbing material that collects stormwater on its surface and does not allow it to filter into the soil, inhibiting the natural water cycle. With this in mind, parking lots have traditionally been built with the primary goal of channeling stormwater into receiving water bodies as quickly as possible, via means such as gutters, drains, and pipes. As a result, runoff that is contaminated with many types of petroleum residues, fertilizers, pesticides, and other pollutants from parking surfaces enters receiving waterways at an unnaturally high rate and volume, negatively impacting the surrounding ecosystem. Hence, parking lots degrade water quality, strain stormwater management systems, consume large amounts of land and resources, and enable urban sprawl.

This EPA resource guide details the effects of parking lot design on water quality and localized water recharge.

Parking lot runoff is a major contributor to nonpoint source pollution of our waterways. Conventional parking lots quickly move stormwater into receiving water bodies. As it flows across pavement, the water picks up pollutants from the surface. This results in large volumes of polluted runoff entering surface waters and groundwater resources, negatively affecting water quality.

…Conventional parking lots consist of large areas of impervious surfaces that do not permit the infiltration of water into the soil. Unlike natural conditions where rainwater filters into the ground, impervious surfaces halt this process, inhibiting a watershed’s natural hydrological cycle in preventing groundwater recharge.

As the post-Recession buildout of commercial and residential development accelerates, this latter effect on water recharge of the local aquifer is of increasing concern in Volusia County.

The water running off the parking areas is also a source of several types of toxic substances and other pollutants.  As detailed in the referenced Green Parking Lot Resource Guide:

Contaminants in parking lot runoff can originate from a variety of sources, including the paving materials used to build them. Recently, the U. S. Geological Survey (USGS) pinpointed parking lot sealants as a significant source of nonpoint source pollution, specifically polycyclic aromatic hydrocarbons, a known carcinogen that can be toxic to fish and wildlife. Automobiles are also a major source of pollutants in parking lot runoff, including antifreeze, oil, hydrocarbons, metals from wearing brake linings, rubber particles and tires, nitrous oxide from car exhaust, and grease.

Flows from the parking lots during rains can also have a negative impact on wildlife in the vicinity of the parking area.  As described in the EPA resource guide:

The contaminants in parking lot runoff also pose a risk to wildlife. Toxic substances from contaminated ground and surface water supplies have the potential to bio accumulate in the tissue of fish and other organisms in the wildlife food chain. It also accumulates in sediments, posing risk to bottom-feeding organisms and their predators.

… Impaired water quality, and increased volume and velocity of runoff, can lead to habitat loss, stress aquatic species, and have an overall negative effect on biological diversity in abutting areas.

Green Parking Lots

greenspace parking lotThere are ways and means to design vehicle parking lots for retail and office developments that mitigate the loss of greenspace; reduce negative effects on local aquifer recharge; and slow the flowrate of runoff and treat the contaminants in the stormwater biologically before it enters the surface waters and the aquifer.  Problems created by the “usual design” approaches and by the flowrates and contaminants in stormwater can be ameliorated by 1) Redesigning parking lots so that they are porous to water, at least partially; 2) using Florida-friendly vegetation; and 3) through using stormwater bioswales to slow and treat the runoff before it enters the aquifer or surface waters.

greenspace parking lotParking Lot Redesign   The surfaces of parking lots may be designed to be water-permeable, allowing for in-place absorption of water.  Some materials and design approaches which allow for permeability include porous asphalt, pervious concrete, using open joint pavers, and applying the principle of the turf grid to increase drainage through the surface of the parking lot.

In addition to materials and drainage-enhancing surface designs, Florida-friendly vegetation can be used for ground cover, edging, open areas and shade.  Grasses, such a St. Augustine grass, are planted to produce that “advertising sheen” but they require large inputs of water, fertilizer and herbicides to thrive. Florida-friendly plants require little maintenance and can survive on natural rainfall.  The photo at left is an example of greenspace parking with a turf grid.

Bioswales   Bioswales are “landscape elements designed to remove silt and pollution from surface runoff water.”  A bioswale has gently-sloping drainage courses and is usually lined with vegetation or riprap which is “”designed to maximize the time water spends in the swale, which aids the trapping of pollutants and silt.”  Bioswale designs allow for treatment of the stormwater before it is released to local watersheds or storm sewers.

Several types of pollutants and contaminants may be collected and, depending upon design factors, treated in place by the bioswales.  These include:

    •    Silt

    •    Polycyclic aromatic hydrocarbons

    •    Pathogens

    •    Macronutrients such as phosphates and nitrates

    •    Mercury, lead, chromium, cadmium and other heavy metals

The recent recovery of financing available for building and development projects in Florida has meant that large-scale retail projects are once again underway in SE Volusia County.  The loss of quality-of-life for local residents which is associated with these developments has been well-documented.  These include increased traffic and safety concerns, loss of greenspace, elevated traffic noise, heat island effects, and an increase in public utility services, the costs of which are borne by the entire community.  A denatured and corporatized landscape has replaced what was once a more gentled, nurturing and life-filled greenspace.  

This corporatization of public spaces and systems degrades the quality-of-life for  local residents. Localized planning and development guidelines are sacrificed to meet corporatized planning and building guidance.  This guidance is narrowly focused on enhancing profits, lowering fiscal costs to the corporate group, and ensuring that the actual costs of the “externalities” are borne by others.  That is, these external costs, which are both fiscal and non-monetary, are passed on to the residents of the counties and municipalities and to the local bio-systems rather than paid by the corporate entity.  

Once the fields, scrub or woodlands are scraped clean, ill-designed and prefabricated buildings are forced onto the landscape and surrounded by asphalt or concrete parking lots, further degrading the environment.  This follow-on degradation of the local environment for both human beings and other living systems serves only the plans of corporate management working in office towers in Toronto, Atlanta, Los Angeles or Dubai.  These managers will see only the projections and reports of traffic and profit, and will not incorporate the concerns of local citizens and living systems in their operative designs.  They serve a corporate entity which has a virtual life of its own.  And this type of self-serving “virtual life” is not the life of local citizens and living systems.  Our municipal  planning commissions need to recall this “local life” and act accordingly, with actions and planning laws and guidance that is life-centered and responsive to local concerns.