Projects > Studies
and Information About York's Rivers, Maine > Salt Marshes
and Tidal Restrictions
York River's approximately 400 acres of salt marsh form valuable
wildlife habitat, and represent about 10% of the salt marsh
in York County. Salt marsh ecosystems are among the
most productive in the world. Marshes themselves face
little threat of development because they are regularly inundated
by the tides. However, they are impacted by nearby development
of uplands, and may be further degraded when fill is used
to make a marsh buildable, either for a road, railroad, or
roads or railroads cross the salt marsh, they restrict the
tidal flow across the marsh. Because the salt marsh relies
on regular cycles of inundation by salt water, restricted
flow can result in degradation of the marshes. Often, invasive
species such as phragmites become prevalent.
are two types of tidal restrictions: Bridges and culverts across
the river or creek channel are restrictive if the size is not
large enough. Also, causeways restrict the flow ideally, a causeway
would have a series of culverts under the entire length of the
has been no formal study of tidal restrictions on the York River
or of the health of the salt marshes.
with Brad Sterl (retired) of Department of Marine Resources.
Interviewed Dec. 1999.
his estimation, the worst tidal restriction is at Cooks Bridge
(Rt. 91), where the road crosses the marsh. Upstream, a large
area of marsh is affected. Prior to the 1960s, there was a
bridge across the channel, which he remembers to be 26'. In
the 1960s, the bridge was replaced by 2 culverts, which do
not allow for sufficient water flow, and which are placed
too high in the road bed, so that they also restrict fish
passage. Although there are other restrictions, he believes
this is the worst one.
believes that Smelt Brook's bridge is big enough so that it
does not restrict tidal flow. There
was a tidal mill on Dolly Gordon Brook; the remains of this
mill may restrict flow.
Brad Sterl in Ogunquit.
on the Lower Barrels Millpond, Becka Roolf. Dec. 1999.
a trip to the Wiggly Bridge, she observed that the Lower Barrells
Millpond was ringed with Phragmites, an invasive species to
saltmarshes. The other visible portions of the York River
had very little or no Phragmites. The causeway with the
Wiggly Bridge is clearly restrictive, and in fact causes a rapid
to be formed during tide changes.
culvert where Rt. 91 crosses Cider Hill Creek also appears to be
placed too high.
Rivers & Trails Program, AMC/National Park Service. 207-725-5028.
a volunteer-based method for determining how restrictive a tidal
crossing is. This handbook is available in its entirety on the Internet,
or in hard copy for $5. The Maine Audubon Society (Rob Bryan) has
also used this method on Scarborough Marsh, in 1999. This is a method
that could be used by the York Rivers Association.
Parker River Clean
Water Association. 978-462-2551.
an overview of tidal marshes, tips on mapping tidal marshes, and
an evaluation system that emphasizes ecology, habitat, and aesthetics.
The section on restoration projects and improving educational/recreational
opportunities is very short, emphasizes common sense, and presents
contact information for relevant state and federal agencies, without
getting into any details what might be involved in restoring a
marsh. Whereas the Parker River guide, above, concentrates
on a fairly technical assessment of one specific type of tidal
marsh degredation, the MAS book is much broader.
Maine Audubon Society, 207-781-6180.
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