Jeff Blecharczyk
PO Box 95
Concord, NH 03302
Email: jblecharczyk@DES.state.nh.us
The Contoocook North Branch River Local
Advisory Committee, (CNBRLAC), has serious concern about the wetlands dredge
and fill permit application of Wal-mart proposed for
the town of
No where in the
plans does it state the percentage of the site which will be covered by
impervious surface.(This is normally put on several of
the plans of the site). The rationale for the legal limit of 30% of the lot
covered with a building, is due to the problems with
the amount of impervious surface. The application states that the building will
cover 23% of the lot. However, with the numerous roadways and parking lots, it
will actually cover over 70% of the site.
In the recently
published USGS Water Quality in the New England Coastal Basins, their
major finding was:
"Degradation
of stream ecosystems appear to occur early in the
process of watershed urbanization. Populations of macroinvertebrate
species, such as mayflies, stoneflies, and caddisflies,
which are sensitive to urban contaminants are reduced
where as little as 3 percent of the land cover in the watershed is urban
and population density is less than 300 people per square mile. Stream
ecosystems are fully degraded where urban areas cover about 20 percent
of the watershed. " ( p. 1 Publication 1226)
Covering over 70%
of this large site on top of Penstock Hill, in addition to the already existing
pavements (of
According to the
plan, all the storm drainage will be routed from throughout the site to the
newly created wetlands on the Northwest corner of the property. Wetlands are
capable of removing sediments, phosphates, and some oil from the runoff.
However, wetlands are not capable of removing either chloride (from the
de-icing of the parking lot), nor can they remove any materials which are
dissolved in the water, such as benzene, toluene, and MBTE). According to the USGS
Water Quality Trends in New England Rivers, published in 2003, "Annual
chloride concentrations in the
Chloride will kill
the vegetation, which will cause further limitation to the wetlands ability to
filter the water. Also, wetlands ability to filter the stormwater
runoff only occurs during the growing season, causing no filtration during the
winter months.
According to the
Wal-mart plan, the runoff will leave the property through two culverts under
the bypass into the wetlands and Shedd Brook near the confluence of Beard
Brook. . Normally, if you change the drainage of an area, a federal alteration
of terrain permit is required, especially when it will drain into a federally
funded (US fish and Wildlife) salmon restoration brook, (Beards Brook) Also the
wetlands on the other side of the bypass is one of the major aquifers for the
town. In these days when drinking water supply is in great demand and a
valuable asset, we think that the town might want to limit degradation of their
aquifers so they can be used as future water supply for either the town or be
sold to other towns.
The application
states that the pond on the south eastern corner and the wetlands on northern
side of the property is manmade, created when the fill
from the bypass was placed there. However, that pond has been in existence for
a much longer time. According to the 1957 USGS Topographical map of 1957, that
area was wetlands back then. According to the Dec. 1953 Hillsborough County
Soil Map, (before old Route9 was relocated slightly to the north) that area is
composed of Whitman stony loam, (poorly drained soils). See copies of maps
attached).
Representatives of the fourteen towns that
serve on this state appointed local advisory committee encourage you to look at
this type of development carefully in light of the above issues.
Signed and submitted on behalf of CNBRLAC
Rodman Zwirner,
Chair