This article from the Winter 2009 edition of Planning Commissioners Journal underscores the benefits of working with nature to manage stormwater:

Managing Stormwater Runoff: A Green Infrastructure Approach
by Lynn Richards, Acting Director for the U.S. Environmental Protection Agency's Development, Community, and Environment Division

...Green infrastructure strategies reduce and manage stormwater through infiltration (water soaking into the ground), capture and reuse (water being stored in a rain barrel or cistern for later use in watering plants or flushing toilets), and evapotranspiration (water being used by trees and plants).

A comprehensive green infrastructure approach to stormwater management seeks to:

* Preserve and enhance natural features, such as undisturbed forests, meadows, wetlands, regional and neighborhood greenways, trails, and other natural areas.

* Recycle land by directing new development to already degraded land, such as parking lots, vacant buildings, and abandoned malls...

While traditional approaches to stormwater management have focused at site-level techniques, green infrastructure takes into account the wide range of development-related issues at the regional, neighborhood, and site-level that affect impervious cover and stormwater runoff...

The single most effective strategy for efficient land use is redeveloping already degraded sites such as abandoned shopping centers or underutilized parking lots rather than paving greenfield sites. [emphasis added]

By redeveloping an underused site that is already paved, the net increase in runoff from development would likely be zero – or it might even decrease, depending on the on-site infiltration practices used...

In conjunction with the stormwater benefits just described, a green infrastructure approach supports an interconnected network of open spaces and natural areas (such as forested areas, greenways, floodplains, and wetlands). This will improve water quality by increasing infiltration and groundwater recharge, while also providing neighborhoods with access to open space for recreational purposes...

Landscaping/Tree Preservation provisions can help reduce runoff by limiting the amount of impervious surface. Are large trees preserved during construction? If not, will they be replaced?...


Sidebar: Some Environmental Benefits of Green Infrastructure

...Heat Impacts Reduced. As paved surfaces gather solar radiation, the heat is transferred to runoff, which can significantly increase the temperature of a creek or pond and disrupt aquatic ecosystems. Green infrastructure can reduce these heat impacts...

Improved Air Quality. Trees and other forms of vegetation that manage stormwater runoff can also help to improve air quality, especially in urban areas...


Sidebar: Making Use of Site Plan Review by Thomas J. DiPietro, Jr.

...Stream Buffer. If your town has a stream buffer ordinance, does that mean your stream’s water quality is protected? Not necessarily. Landscaping requirements within buffers are often needed to ensure that the buffer provides its intended functions. Existing vegetation should not be cleared during construction and the area should not be converted into lawn. In addition, items can end up within stream buffers that aren’t shown on the site plan. Examples include walking paths, picnic tables, compost bins, and dumpsters. It is a good idea to specify that stream buffers are to remain in their natural condition and that modification and clearing is prohibited.

The North Street infill project proposed by Kohl Construction would take place in one of the few groves of mature trees left in downtown Northampton. Many large trees would be cut down, with a great deal of disturbance to the buffer zone around Millyard Brook and its surrounding wetlands. Well-intentioned wetlands "improvement" (removal of invasive species) might increase this disturbance even more. Meanwhile, large buildings and paved surfaces on nearby King Street languish either unused or underused.


See also:

Gazette Reports on Kohl Condo Hearings; Pictures of the Latest Proposal; Conservation Staff Report; HYLA Critique
At the Conservation Commission hearing, Land Use and Conservation Planner Bruce Young mentioned that he finds many properties around Northampton are out of compliance with wetlands protection agreements. Enforcement is a tedious process that is consuming a large amount of his time. People are disregarding no-disturb boundaries, mowing where they shouldn't mow, etc. This is entirely consistent with scientific findings that wetlands buffers of less than 50 feet are generally ineffective at protecting wetlands. The answer, as one Conservation Commissioner put it, is "space"...

[Dr. Bryan S. Windmiller of HYLA Ecological Services:] ...The shade of a closed-canopy forest produces very different physical conditions at ground level than experienced in adjacent open areas.   Open areas are windier and drier at ground level, have sharper temperature fluctuations, and much deeper frost lines than adjacent woods.  Rain strikes the ground with greater erosive force in open areas.  These differences do not end abruptly at the forest edge but are propagated well into the woods.  Light levels near a forest edge return to normal (i.e. similar to forest interior) in only a few meters from the edge (e.g. <20 feet), but wind patterns, turbulence, and reduced humidity typically extend from 0.5 to several times the average height of canopy trees (e.g. >>30 feet into the North Street Woods, Richard T.T. Forman,  Land Mosaics, 1995. Pp. 88-89).   These altered physical conditions increase the penetration of invasive plant seeds into the forest, and stress forest interior adapted native forest floor plants...

People apply numerous toxic substances to their lawns, sheds, and home exteriors.  Some of these substances are water soluble and readily transported into adjacent wetlands by runoff or via infiltration into groundwater and then groundwater discharge into wetlands at low seasonal water levels.  Other substances are readily adsorbed onto dust particles.  Dust is to be found in abundance around newly disturbed house sites and the dust is blown many yards into nearby woodlands on the altered wind currents near the forest edge.  As a result, wetlands located in close proximity to residential areas and with little intervening natural vegetated buffer are prone to elevated levels of contamination, regardless of the effectiveness of stormwater detention systems...

The intended use of herbicides by the applicant to control Japanese knotweed (Polygonum cuspidatum) will moreover result in the pollution of the wetland with herbicides and their toxic surfactant agents.  The commonly used herbicide glyphosate (Rodeo and Roundup) has been shown to be highly toxic to amphibians, for example, in numerous papers by Rick Relyea and colleagues (see summary at: http://www.medicalnewstoday.com/articles/22159.php).   Japanese knotweed and multiflora rose (Rosa multiflora) are furthermore difficult to eradicate, even with herbicides.  To do so will require significant doses of herbicide applied many times.

In the end, such schemes are likely only to result in further degradation of the wetland system...

Smart Growth vs. "Smart Growth"
Smart Growth, in its full flower, contains numerous protections, safeguards, checks and balances. The Urban Land Institute includes the following among its Ten Principles for Smart Growth on the Suburban Fringe (PDF):

Identify and Sustain Green Infrastructure
...Green infrastructure networks encompass a wide range of landscape elements, including natural areas such as wetlands, woodlands, waterways, and habitat; public and private conservation lands such as nature preserves, wildlife corridors, greenways, and parks; and public and private working lands of conservation value such as forests, farms, and ranches. It also incorporates outdoor recreation and trail networks as well as cultural and historic resources that provide the community its character.

When we use the word infrastructure, we usually think of built infrastructure such as roads, electric power lines, and water systems and social infrastructure such as schools, hospitals, and libraries. The concept of green infrastructure, however, elevates air, land, and water to an equal footing with built infrastructure and transforms open space from “nice to have” to “must have.” At the same time, green infrastructure helps provide a framework for growth by identifying the places that should not be built on, putting a stop to the project-by-project battles that developers face over open space and the environment...

The problems with Kohl's condo proposal include:

* It threatens green infrastructure by putting roads and structures as close as 35 feet or less to a wetland. Scientific evidence indicates that substantial disturbance within 50 feet puts wetland ecology at risk and threatens water quality. In addition, the condos themselves appear to be at risk of flooding...

Our Ad in Today's Gazette: A Review of Our Objections to the Kohl Condo Proposal
True Smart Growth respects green infrastructure, such as trees and wetlands. These greenspaces filter the air, reduce the urban heat island effect, enhance property values and moderate stormwater flows, and they do it inexpensively. Urban greenspace is associated with improved physical and mental health and greater social cohesion in neighborhoods.

More Detail on the Zero Lot Line Proposed Changes; Evaluating Infill Impacts
The maximum possible consequences from the proposed changes need to be spelled out, including the potential percentage increase in impervious surface and potential loss of tree canopy, broken out by ward. As with the new wetlands ordinance, it's not enough to evaluate the impacts of new rules project by project. Long-term impacts at the ward and city level must also be evaluated.

More generally, the extent of impervious surface, tree canopy, and other critical metrics should be monitored ward by ward and reported to the public on an annual basis.

Gazette: "'Brownfields' law altering landscape"
Today's Gazette includes an AP report on the kind of smart growth we think is great: brownfields revitalization. Reusing buildings and paved areas, as opposed to knocking down urban trees and encroaching on wetlands, is infilling the right way.

Syd Gernstein: "Brownfields Revitalization Cuts Urban Blight, Suburban Sprawl"
...One obvious benefit of brownfield redevelopment is that it eases the need for metropolitan expansion. It allows a city to grow by making better use of the space it already occupies...

MassDEP Brownfields Success Stories

EPA: Brownfields Success Stories