Airport Master Plan 2012 - City of Waterville

Obstruction removal could have potential impacts on water quality due to the potential for increase
erosion and sediment loading to surface water resulting from vegetation removal.
5.4.1 Surface Water
Section 401 of the Federal Clean Water Act (1972) requires applicants for Federal permits for projects
that result in a discharge to waters (including wetlands) of the State of Maine to obtain a State Water
Quality Certification (WQC). Applicable activities that likely will require a State Water Quality
Certification (WQC) include those involving any filling of wetlands and/or the waters of the State of
Maine. The only proposed projects that may impact wetlands are obstruction removal on/in the vicinity of
the Airport and apron and hangar development which may increase surface water runoff. Since erosion
controls will be maintained throughout the duration of any proposed projects, and these projects will be
implemented in a manner intended to minimize impacts on water quality, adverse impacts to surface
water are not expected to occur during or following completion of the proposed projects.
5.4.2 Ground Water
As identified in the baseline conditions, the Airport is situated in an area with moderate to low or no
potential groundwater yield and is not located over or near any mapped sand and gravel aquifer which
could be utilized as a municipal ground water supply. All proposed development will utilize municipal
water supply and wastewater disposal systems where discharge of water or pollutants to groundwater is
not anticipated. Therefore, no new sources of groundwater contamination are expected as a result of any
proposed development.
5.4.3 Drinking Water
There will be no change in the use of petroleum or other chemicals in paved areas or other areas of the
Airport as a result of any proposed project. Increased impervious surface within a specific watershed at
Waterville Airport could result in slightly less direct recharge to underlying subsurface materials. Based
on the lack of significant adverse effects to surface water and groundwater described in Sections 5.4.1 and
5.4.2, no significant adverse impacts to drinking water on the Airport property or its vicinity are
anticipated as a result of any proposed projects.
5.4.4 Stormwater
Stormwater produces runoff that begins when rainfall has no place else to go, when soil and vegetation
can no longer absorb and store stormwater. Maine receives approximately 42 inches of precipitation a
year (MaineDOT BMP for Erosion and Sediment Control), in the form of rain or snow and the volume
and rate of runoff is directly related to the duration and intensity of this precipitation. The State of Maine
recommends using Best Management Practices (BMPs) in conjunction with Low Impact Development to
minimize the volume and rates of runoff leaving a site.
Additionally, airport operations are regulated by the U.S. Environmental Protection Agency under the
National Pollutant Discharge Elimination System (NPDES) authorized by Section 402 of the Clean Water
Act. The NPDES permit program controls water pollution by regulating “point sources,” i.e., pipes, manmade
ditches and so on, that discharge pollutants into waters of the United States.
As described in previous airport development permit applications (Application for Permit Modification
for Airport Improvement Projects, March 2004), the Airport uses several drainage areas to model
stormwater runoff. Watershed 1 contains the business park and the north-west portion of the Airport. All
runoff generated in Watershed 1 drains to a stream that traverses the site from north to south. Watersheds
The City of Waterville Maine
Environmental Review – Page 5-4
Airport Solutions Group, LLC & The Louis Berger Group, Inc. December 2011