At the April 18 public hearing on a new wetland law, Yorktown Supervisor Michael Grace said he thought wetland function and/or value (he incorrectly used the two terms interchangeably) should be part of the definition of a protected wetland, making statements to the effect that, “It’s not just size; function should somehow be involved.”  He seemed willing to keep the 1,000-square-foot minimum size for a protected wetland in the current law if a function/value measurement was incorporated into the definition.

In his comments after the June 20 public hearing on the 2016 Tree Law amendment, Supervisor Grace brought up wetlands functions again, calling the lack of wetland functional analyses a “major ecological flaw” in the Wetland Law.

While the supervisor’s emphasis on function and value is to be applauded as both far-thinking and scientifically sound, the proposed April Wetland Law failed to incorporate either function or value in a meaningful or coherent way. The law also incorrectly conflated the definition of a wetland with size, function and value.

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Distinguishing Between Wetland Function and Wetland Value

Wetland ecological functions are the natural processes (physical, chemical and biological) associated with wetlands, i.e. their role in the natural environment—what they do. Wetland values can be thought of as the “goods and services” wetlands provide to humans and the societal values placed on these services, economic or aesthetic—why we care. For example, one wetland function is surface water storage and release. The value of that wetland function to humans is the moderation of storm water peaks, reducing potential flood damage.

During the April public hearing, Supervisor Grace used the terms “high functioning and low functioning wetlands.” Obviously wetlands don’t each carry out all functions equally, so these terms have no meaning unless a specific function is attached.

Defining What Is a Wetland

Wetlands are defined by the presence of wetland soils, hydrology and/or vegetation. Once defined, a size parameter is sometimes added to a law to identify the wetlands that are to be protected and regulated. While soil, vegetation, hydrology and size are physical characteristics that can be quickly, accurately and objectively measured in the field, function and value are subjective measures that can’t be part of a legal definition. A wetland is a wetland is a wetland, no matter what its size, function or value in the natural environment.

Complications of Using Function and/or Value When Defining a Wetland

Consider the following complications of trying to include function and/or value parameters in the definition of a protected wetland:

• Which of the long list of possible wetland functions would be written into the definition of a protected wetland, keeping in mind that wetlands don’t carry out all functions equally?

• How would these parameters be measured? Who would do the assessment? Does town staff have the technical expertise and time to do functional assessments? 

• Wetland Functional Value Assessments, their titles notwithstanding, don’t provide information about the value of wetland functions, so how will values be determined for defining a protected wetland? Would the public get to weigh in on the societal values assigned to wetland functions?

Function and value also need to be incorporated into a revised Tree Law.

At the June 20 Tree Law amendment public hearing, Supervisor Grace emphasized his interest in extending a functional approach to tree protection, insisting that analyses of how trees function as habitat and the ecological impact of trees should be components of the Tree Law. Again, this approach is to be applauded.

The problem, though, is that notwithstanding Supervisor Grace’s professed interest in the ecological functions of trees, the 2016 Tree Law does not recognize the varied roles of trees in our community, and it eliminates regulations tailored to the different functions of trees, regulations that were in the repealed 2010 law.

The Tree Law should protect and regulate not just the trees as trunks, branches and leaves, but also how the trees interact and function in a dynamic ecological community of plants and animals. In fact, forests and wetlands carry out some of the same functions and should be valued and protected in line with those similarities. The 2016 replacement tree law doesn’t even recognize forests as multi-functioning ecosystems.

If the town board intends to use functions and values in defining, regulating and protecting wetlands, trees and forests, then this goal has to be clearly stated in the environmental laws. The town board needs to think through its policy and decide how the town will value the functions of its natural resources.

Linda Miller, PhD, is a retired environmental consultant, professor of environmental science and Yorktown Conservation Board member.