Watershed Science Centre. Trent University. Symons Campus 1600 West Bank Drive, Peterborough, Ontario K9J 7B8. www.trentu.ca/wsc Preliminary Identification of Data and Knowledge Gaps, and Research Needs: Theme 1: Intake Protection Zones in the Great Lakes Basin Proceedings from the Source Water Protection Research Workshop, September 14 th , 2006, Etobicoke, Ontario November 23 rd , 2006 Revised: August, 2007 REPORT PREPARED BY: Gordon Balch Research Associate Watershed Science Centre Trent University Email: [email protected]Phone: 705-748-1011, x 7071 Fax: 705‐748‐1022 The information contained in this report is the result of consultation efforts and does not necessarily reflect the opinions or priorities of the Province of Ontario
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Watershed Science Centre. Trent University. Symons Campus
1600 West Bank Drive, Peterborough, Ontario K9J 7B8.
www.trentu.ca/wsc
Preliminary Identification of Data and Knowledge Gaps, and Research Needs: Theme 1: Intake Protection Zones in the Great Lakes Basin Proceedings from the Source Water Protection Research Workshop,
September 14th, 2006, Etobicoke, Ontario
November 23rd, 2006
Revised: August, 2007 REPORT PREPARED BY: Gordon Balch Research Associate Watershed Science Centre Trent University Email: [email protected] Phone: 705-748-1011, x 7071 Fax: 705‐748‐1022
The information contained in this report is the result of consultation efforts and does not necessarily reflect the opinions or priorities of the Province of Ontario
WSC 2006:.SWP-Theme I (Proceedings of Sept 14th, 2006 Workshop)
Table of Contents
Email: gbalch@trentu.ca..............................................................................................................1 Phone: 705-748-1011, x 7071......................................................................................................1 Table of Contents .........................................................................................................................2 1.0 Summary..........................................................................................................................3 2.0 Introduction......................................................................................................................6
2.1 Goals of the September 14th, 2006 workshop ......................................................7 2.2 Background to workshop .....................................................................................7
3.0 Organization of Workshop..............................................................................................9 4.0 Summary of Workshop Discussions............................................................................ 10
4.1 Refinement and focusing of key recommendations from February 2006 workshop.......................................................................................................................10
4.1.1: Should protection be directed at acute spill events or chronic cumulative impacts?...................................................................................10 4.1.2: What is the best method for IPZ-2 delineation within the Great Lakes Basin? ..............................................................................................11 4.1.3: Source water protection efforts in the Great Lakes basin require collaboration with USA counterparts.........................................................15 4.1.4: Better resolution is required to identify threats from un-monitored point and non-point sources for which water quality is poorly characterized. .............................................................................................15 4.1.5: More data is needed in order to evaluate the risks associated with microbial pathogens, chemicals of emerging concern and cumulative impacts .......................................................................................................18 4.1.6: Groundwater / surface water interactions need better resolution ....19
4.2 Identification of existing sources of information...............................................19 4.3 Identification of key research needs related to Intake Protection Zones (IPZs)20 4.4 Identification of potential research partners and sources of funding.................22 4.5 Concluding Remarks..........................................................................................22
5.0 Appendices ................................................................................................................... 24 5.1 Description of the Watershed Science Centre and role in source water protection ......................................................................................................................24 5.2 Four themes identified in February 2006 workshop ..........................................25 5.3 List of September 14th, 2006 workshop participants and affiliations ................26
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WSC 2006:.SWP-Theme I (Proceedings of Sept 14th, 2006 Workshop)
1.0 Summary
A one day focus group session was held on September 14th
, 2006 in Etobicoke, Ontario to
discuss the data gaps and research needs required for the boundary delineation of intake
protection zones (IPZs) within the Great Lakes basin. In attendance at the workshop were
23 participants, of which 18 were invited and 5 were from the Watershed Science Centre
(WSC) at Trent University. As indicated in the list of attendees (Section 5.3), the
workshop participants were from provincial government agencies (i.e. Ontario Ministry
of the Environment - OMOE, Ontario Ministry of Natural Resources - OMNR,
Conservation Authorities - CAs), municipal governments, and a non-government
organization (Canadian Environmental Law Association - CELA) plus academia (i.e.
Trent University, Queen’s University).
A general consensus emerged at the focus session suggesting that the method for
delineation of Intake Protection Zones (as outlined in the OMOE Source Water
Protection Guidance Modules) is most appropriate for the protection of drinking water
from hazards related to spills or releases of contaminants (chemical, pathogenic, nuclear)
which have the potential through hydrodynamic processes to reach a zone of water
surrounding the drinking water intake crib within a relatively short period of time (e.g.,
2h). The approach outlined in the OMOE guidance modules is intended to provide a
mechanism for delineating a zone around a specific drinking water intake. The outer
boundary of the zone is determined by employing a reverse particle tracking approach
using a predetermined time-of-travel (TOT) between the intake crib and the boundary of
the IPZ (e.g., IPZ-2). The purpose of the IPZ is to delineate a zone in which all threats are
identified and the risks associated with each threat are evaluated. Participants also
expressed their view that this approach was less appropriate for identifying the threats
(chronic, cumulative) to drinking water that are associated with overall degradation of
water quality arising from cumulative impacts of low level contaminants which may
individually be at concentrations below provincial guidelines, but cumulatively may still
pose an as-of-yet unidentified threat and thus an un-assessed risk. Threats associated with
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WSC 2006:.SWP-Theme I (Proceedings of Sept 14th, 2006 Workshop)
the potential for chronic exposures to low levels of emerging chemicals of concern and or
the presence of microbial pathogens in source waters are much more difficult to identify
through a time-of-travel, event-driven approach than are the threats associated with acute
spill events. This is particularly true when the sources of chronic / cumulative threats are
either distant (e.g. originating outside of source water protection areas) or diffuse (e.g.
non-point sources), or transient (spatial / temporal). Compounding this problem is that
human health assessments and regulatory guidelines do not exist for many of the
emerging contaminants of concern.
The OMOE guidance modules regarding the delineation of IPZs within the Great Lakes
basin employ both a fixed radius for IPZ-1 (primary zone of protection) and a time-of-
travel for IPZ-2 (secondary zone of protection) approach. The 1 km fixed radius of IPZ-1
constitutes the most vulnerable zone of water around the drinking water intake, thus the
most restrictive for human activity, with the premise that Drinking Water Treatment Plant
(DWTP) operators may not have adequate time to respond to contaminant releases within
this zone. The IPZ-2 is intended to provide additional protection from threats that can be
potentially transported by hydrodynamic processes to the water intake. The outer
boundary of IPZ-2 is based on a time-of-travel principle. The minimal time parameter
suggested by the OMOE guidance modules is 2h, which may be increased if necessary to
ensure the DWTP operators have sufficient warning necessary for taking corrective
action.
Workshop participants recognized the hydrodynamic complexities associated with the
Great Lake waters and as such had difficulty coming to any consensus regarding the best
approach for delineation of IPZ-2 boundaries. In addition, there was a general opinion
that dilution effects within the open water zone of the Great Lakes would, in all but the
most severe spill events, dilute chemical contaminants to levels below provincial
Drinking Water Quality Guidelines. Participants generally agreed that the spatial and
temporal variability of hydrodynamic processes within nearshore zone, plus the inability
to assess cumulative risks from the chronic exposure to low concentrations of emerging 4
WSC 2006:.SWP-Theme I (Proceedings of Sept 14th, 2006 Workshop)
chemicals complicates the delineation of IPZs. As such, more research is needed to better
characterize hydrodynamic processes in order to refine the criteria used for the
delineation of IPZs which in turn will be used as a method facilitating the inventory of
potential threats to drinking water supplies within the nearshore zone
Participants generally agreed that there are presently a variety of computerized
hydrodynamic models (e.g. 2-dimentional, 3-dimentional) in existence which could be
employed for IPZ boundary delineation required to identify acute threats (i.e., not
chronic, cumulative threats). The utility of these models is however, often unknown and
possibly hampered from a lack of model calibration and validation to specific site
conditions. The application of these models throughout the Great Lakes basin can be
impeded by: i) a lack of funding and local expertise necessary to calibrate the models to
specific locations, ii) the lack of a coordinating administrative structure to ensure
standardization of modelling efforts among IPZs and source water protection areas, and
iii) the identification of appropriate monitoring surrogates of contamination to assess
contaminant movement and evaluate risks associated with point source discharges (e.g.,
wastewater effluent) or non-point source releases (e.g. microbial indicators of human
pathogens) as a means to validate model predictions. For best results, participants also
expressed that hydrodynamic models should be coupled (when possible) with information
concerning land use practices, overland wet flow events, and lake water / ground water
interactions to reflect that contaminant movement is influenced not only by in-lake
hydrodynamic processes but also includes aspects of overland transport and groundwater
movement.
No one municipality, Conservation Authority or government agency has the resources
needed to address these impediments in a coordinated manner across the Great Lakes
basin. Implementation of such an approach would be best accomplished through strong
leadership arising from the cooperative effort of multiple government agencies.
Participants identified a need to develop a mechanism to involve all levels of government
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WSC 2006:.SWP-Theme I (Proceedings of Sept 14th, 2006 Workshop)
in Canada and the USA in a coordinated effort to address model development, the
formulation of guidelines for model selection, the identification of threats and the
evaluations of risks associated with source water protection.
The workshop participants identified key sources of information and current research
initiatives which provided a good starting point for the Watershed Science Centre in
evaluating science gaps, potential research partners and sources of funding. Information
leads and contacts arising at the focus session will be explored in depth during the next
months. Outcomes from this process will be summarized and documented in a final
report identifying the data gaps and science needs for source water protection.
2.0 Introduction
This report summarizes the discussions which took place during a one day focus group
session (September 2006) which gathered source water practitioners and Great Lakes
experts to discuss issues related to the delineation of intake protection zones within the
surface waters of the Great Lakes basin. IPZ delineation within the Great Lakes is
complex because of the scale of the system, integration of the lakes and the potential for
the transport of water quality impacts from a wide geographical area which is far beyond
a single source protection area. Site specific hydrodynamic processes in the nearshore
zone complicate the predictions of water movements. The identification drinking water
concerns and potential threats to IPZs in the Great Lakes was identified as a research
priority during a previous February, 2006 workshop organized by the OMNR, OMOE,
and Conservation Ontario in February, 2006.
The focus group session in September, 2006 was organized and hosted by the Watershed
Science Centre (WSC) of Trent University. The WSC was established from a partnership
of Trent University with the Ontario Ministry of Natural Resources, Sir Sandford
Fleming College and the Ontario Ministry of the Environment. Recently, the mandate of
the WSC was broadened in its watershed management emphasis to include a specific
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WSC 2006:.SWP-Theme I (Proceedings of Sept 14th, 2006 Workshop) focus on the identification of knowledge gaps and science needs pertinent to source water
protection (SWP), and the transfer of knowledge in areas of risk mitigation and watershed
management as it relates to sources of drinking water. A short description of the WSC
and its role in SWP is provided in Appendix (Section 5.1). A two day workshop of SWP
practitioners held in February, 2006 broadly defined the research needs for SWP within
four major themes. Those themes are also listed in the Appendix (Section 5.2). The
purpose of the September, 2006 meeting was to further refine discussions within one of
the four themes, that is: Theme 1 - Intake Protection Zones (IPZs). In general terms,
the focus session began where the February 2006 workshop ended.
2.1 Goals of the September 14th, 2006 workshop
The goals of this workshop were to:
1. Refine and focus some of the key recommendations related to IPZs identified
at the February meeting. These key recommendations are presented below
(Section 2.2).
2. Identify existing sources of information (literature, data bases, tools) which
can be later reviewed by the WSC to determine gaps in information and data.
3. Identify the key research needs related to IPZs.
4. Identify potential research partners and sources of funding that can be
leveraged against the resources of the WSC and its Partners in order to
facilitate the work of future research projects aimed at addressing knowledge
gaps.
2.2 Background to workshop
Intake protection zones refer to areas (primarily surface waters, but may include portions
of the shoreline) that surround the intakes for municipal residential drinking water
systems. Draft guidance documents developed by the OMOE delineate four types of
IPZs, namely i) Great Lakes, ii) Great Lakes connecting channels, iii) inland
rivers/streams, and iv) inland lakes. The draft guidance documents can be reviewed at the
following website. http://www.ene.gov.on.ca/envision/water/cwa-guidance.htm