Projects > Studies
and Information About York's Rivers, Maine > Water Quality
quality in the York River is generally quite good. Water quality
supports fishing and swimming, although sewage discharges prevent
the harvesting of shellfish. These uses are prevented when E.
coli bacteria levels are too high.
bacterial pollution is often the type of pollution of greatest concern
to people, aquatic life generally isn't terribly bothered by bacteria.
Fish and other aquatic life depend more on high levels of dissolved
oxygen, appropriate temperatures, neutral pH (rather than acid rain),
nutrients in the proper balance, and natural flows with seasonal
variation. Accordingly, a comprehensive water quality monitoring
program looks at many other factors.
the most intensive studies of the York River estuary has been by
the Maine Department of Marine Resources and the York Conservation
Commission. Both groups have focused primarily on bacterial
pollution (which results in the most direct threat to shellfishing).
Both groups have also taken some other measurements, including temperature,
dissolved oxygen, and salinity. Although water quality does
limit recreational shellfishing, steps are being taken to prevent
point-source discharges of human sewage to the river. Once
these are fixed, a more intensive survey of non-point sources of
bacterial pollution may be desirable, particularly if the river
continues not to meet shellfishing water quality standards.
Although non-point source pollution is probably the greatest threat
to the health of the York River, little upstream monitoring has
been done to determine which areas are most threatened by non-point
source pollution, particularly in the freshwater portions of the
No water quality monitoring has been done with the specific interest
of categorizing the river for fish habitat.
No biomonitoring has been done in the York River (although some
has been done for the sediments, see T1.)
Possible biomonitoring could include:
Tissue analysis of blue mussels for PCBs and dioxins.
Maine DEP has done these samples in other areas, and is likely
interested in doing the tests on mussels from the York River. To
encourage this, contact John
Macroinvertebrate surveys. This method uses freshwater macroinvertebrates
as indicators of water quality, and is gaining favor as a
water quality monitoring method across the U.S. Volunteer
programs may involve local high school classes; the Maine
DEP also uses this method, but has not sampled in the York
In order to reopen closed clam flats, a more intensive study of
bacterial pollution may be useful, particularly once overboard
sewage discharges have been corrected by local homeowners and
businesses. Once these problems are fixed, non-point source
pollution will be the largest source of bacterial pollution.
It is not known what impact the interstate and associated roadways
have on the York River.
The existing water quality data is not in a single database or
GIS system. In order to track long-term trends, as well
as possible gradual decline from non-point source pollution, it
would be desirable to put all data in one place for analysis.
This would also facilitate presentation of any sub-standard areas
to DEP for inclusion in the Impaired Waters list.
water bodies have a classification under the Federal Clean Water
Act, based on classification standards established at the state
level. The states compile a list of waters that do not meet their
standards; this is revised ever 2 years.
River Water Quality Classifications:
A Ponds used for drinking water: Boulter Pond, Belle Marsh
B All other freshwater portions of the river.
SB (Saline B) Estuary portion of the river.
List of Impaired Waters (303d List):
Brook - Class B. Impaired due to low dissolved oxygen
(DO) 2-3 ppm. Class B waters should have at least 7 ppm.
The low DO is because Belle Marsh Reservoir releases water from
the bottom of the impoundment: water from the bottom of lakes
is usually depleted of oxygen. This may affect the smelt run,
and other fish/aquatic life, downstream.
Harbor - Class SB. Impaired due to bacterial contamination
from human sewage, via the permitted overboard discharges.
Pond - Class B. Impaired due to nutrients / algal blooms.
The source is unknown.
Pond - Classified as "Threatened" due to expected land use
changes in the watershed over the next 10 years, expect an increase
in eutrophication from excess nutrients in rainwater runoff.
Revisions to the List of Impaired Waters:
The next revision to the 303d list will be in April 2000. DEP
does not anticipate having any new data for the York River. The
York Rivers Association may wish to follow this process, and encourage
DEP to add other impaired waters, or to encourage DEP to develop
management plans to reduce pollution to the impaired bodies.
a complete discussion of the Clean Water Act, the 303d List, and
how Total Maximum Daily Loads (of pollution) regulations can be
used to combat non-point source pollution, obtain a copy of River
Network's excellent manual: The
Clean Water Act, an Owner's Guide.
Maine's contact for the 303d list is Dave
Courtemanch, DEP Augusta. 207-287-7789.
report is based on fecal coliform data collected from 1993-1998,
and delineates open and closed shellfishing areas. Includes text
of DMR regulations regarding shellfishing in York and maps of open
and closed areas. Data includes raw data from 1993-98 for fecal
coliforms/100 mL, shoreline survey narratives, and a map of potential
pollution sources. Information about York Waste Water Treatment
Laura Livingston. Maine Department of Marine Resources.
report, not written for the layperson. This study calculates the
total volume of the estuaries/embayments, determines their flushing
rates, and calculates ocean input compared to annual runoff from
the watershed. The report indicates that York Harbor takes
about 17.5 hours to flush.
study also measured water quality parameters. Here is a summary
of data from Table 1b (1996), which presents the average measurements
for York Harbor.
oxygen was relatively low in the York Harbor, with a minimum DO
of 5.28 mg/l (67.9% of saturation), and a mean of 6.83 mg/l (86.8%
data, working with high school, over 5 years at a total of 19 sites
(not all sites were sampled all years). Total number of samples
at each site ranged from 52 to 2. Most sample sites were along the
Little River, which runs through the more populated section of York.
Three sites were on the York River: Upper Barrels Mill Pond, Lower
Barrels Mill Pond and Wiggly Bridge.
Conservation Commission Monitoring Home Page. (If that link
has expired, you can find the new page by going to the York
Conservation Commission link from Town Government page.)
one-time monitoring for Boulter Pond consisted entirely of using
a secchi disk to measure water clarity. In 1977, the water
clarity was 3 meters. This report is not very useful, because
not only are there no other data to compare, but it also doesn't
indicate where on the pond the measurement was taken. Maine's
DEP program has not done any other monitoring in the watershed that
was on file.
This information was obtained from Susan Davies, Maine DEP Biomonitoring.
data from 7 sites on the York River, ranging from freshwater to
the estuary, and measured dissolved oxygen, temperature and salinity,
both early in the morning and in the afternoon in late July 1992.
is the source of this data? It was originally filed along
with the Dissolved Oxygen study, Q3 above. Are there data
from other monitoring dates at the same sites?)
outreach program was first developed in the early 1990s, and has
been duplicated across the country. It consists of a traveling
slideshow presentation for municipal officials. The presentation
uses GIS maps, build-out analyses, and predictors of water quality
to show the impact of non-point source pollution on watersheds.
The Coastal Mosaic project is a NEMO-like project. However,
the original is worth taking a look at!
entire slideshow is available on the web, or you can download a
Outreach for Municipal Officials home page.
series of photocopied fact sheets are quite lacking in visual design
appeal, but provide basic technical information about watersheds
and prevention of non-point source pollution.
to the State Coastal Program, the York River is a priority watershed
for non-point source pollution reduction.
DEP does not include it as a sensitive watershed for the Stormwater
Management Law. Sensitive or threatened watersheds require additional
stormwater permits for projects with 20,000 ft. or more of impervious
surface. The York River watershed has not been included because
it is not near the threshold for a percent of impervious surface
that would cause water quality to be threatened.
town could enact stormwater quality standards that are stricter
than what DEP requires; it might be possible for the towns of the
York River Watershed to proactively require permits according to
the standard DEP rule for priority watersheds.
Maine DEP, Jeff Dennis.
DEP provides a wealth of information about watershed planning and
preventing non-point source pollution.
Look at their web site, or call Norman Marcotte 207-287-7727.
EPA manual was developed along with River Watch Network, a national
volunteer monitoring assistance organization. It includes
sample Quality Assurance Plans, as well as information on why monitor
most common parameters that are part of a volunteer water quality
Volunteer Stream Monitoring - see especially Chapter 5.
to Pollution Studies: Toxics
to the Index.