Lower Welland River Characterization Report - Niagara Peninsula ...

Lower Welland River Study Area
Characterization Report
Initiatives to address these priorities are currently being coordinated by the lead RAP agencies
through the new RAP implementation framework presented in the Stage 2 Update report.
Implementation of the Niagara River RAP monitoring plan will allow comprehensive and defensible
reports on the progress of ecosystem recovery, and will ultimately provide the evidence for
delisting the Niagara River watershed as a Great Lakes Area of Concern (Cromie 2009).
NPCA Water Quality Monitoring Program
The Ontario Ministry of Environment (MOE) has established a set of Provincial Water Quality
Objectives (PWQO) that are intended to be used to guide respective agencies when making water
quality management decisions. The surface water quality management goal is “To ensure that the
surface waters of the province are of a quality which is satisfactory for aquatic life and recreation”
[MOE 1994 (Section 3.1)]. Table 8 summarizes indicator parameters that are the most useful in
assessing relative stream water quality. They include: total phosphorus, nitrate, copper, lead, zinc,
Escherichia coli, chloride, suspended solids and benthic invertebrates (NPCA 2010a). These
parameters are useful indicators but other non-chemical factors such as for example, loss of
habitat, sedimentation, and indigenous species must also be considered when assessing
ecosystem health.
Table 8: Water Quality Parameters (as modified from NPCA 2010a)
Category Indicator Parameter Objective Reference
Nutrients Total Phosphorus 0.03 mg/L PWQO (MOE 1994)
Nutrients Nitrate 13 mg/L CWQG (CCME 2007)
Metals Copper 0.005 mg/L PWQO (MOE 1994)
Metals Lead 0.005 mg/L PWQO (MOE 1994)
Metals Zinc 0.02 mg/L PWQO (MOE 1994)
Microbiological Escherichia coli 100 counts/100mL PWQO (MOE 1994)
Other Chloride 100 mg/L CWQG (CCME 2005)
Other Suspended Solids 25 mg/L BC MOE (2001)
Biological Benthic Invertebrates Unimpaired BioMAP (Griffiths 1999)
The Water Quality Index (WQI) is used by the NPCA to summarize water quality data collected
from NPCA surface water quality monitoring stations for reporting and communication purposes.
The WQI was developed by a sub-committee established under the Canadian Council for Ministers
of the Environment (CCME) Water Quality Guidelines Task Group to provide a convenient means
of summarizing complex water quality information and communicating it to the public (CCME
2001). The WQI incorporates the number of parameters where water quality objectives have been
exceeded, the frequency of exceedances within each parameter, and the amplitude of each
exceedance (NPCA 2010a). The index produces a number between 0 and 100 which represents
the worst and best water quality, respectively. These numbers are divided into five descriptive
categories that range from poor to excellent (Table 9).
Water quality is monitored at two stations in the Lower Welland River study area; station WR010
and station TC001 (Figure 11). Station WR010 is located where the Welland River exits the
second siphon under the Welland Canal. Station WR010 has a Water Quality Index (WQI) rating of
Marginal, which is the highest WQI rating achieved in the Welland River watershed in 2009. Water
quality is improved at this site by direct mixing with backflow from the Niagara River as it is
redirected up the Welland River as part of the hydroelectric operations and from flow-through at
the Welland Water Treatment Plant where water from the Old Welland Canal flows into the
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