As early as 1961, it was recognized by Fisheries and Oceans Canada (“DFO”) that fish passage would be an issue if a causeway was built across the Petitcodiac River. Consequently, DFO required that a fishway be included in the structure. However, the construction of the causeway with the fishway resulted in fish passage issues from the outset. The fishway proved ineffective for all fish species that require passage for life cycle purposes, including the Inner Bay of Fundy Atlantic salmon that is now also protected under the Species at Risk Act because of declining numbers. Subsequent modifications to the fishway and gate management have failed to provide a solution to the fish passage issues. The continual efforts to address fish passage issues have largely failed and thus the facility has not met the intent of the original requirement for a fishway in the structure, and also continues to not meet the requirements of Section 20 of the Fisheries Act.

The history of the causeway was previously reviewed by Eugene Niles, Special Advisor to the Minister of Fisheries and Oceans, in his report of February 9, 2001 (the “Niles Report”; Niles, 2001). The Niles Report concluded that fish passage through the causeway gates and fishway has been problematic and continues to be problematic to this day in spite of numerous changes in operational procedures and modifications to the gates and fishway. The Niles Report recommended four possible options to address the fish passage issue.

Following a variety of separate reports and actions, and based on the recommendations as presented in the Niles Report, it was resolved that an EIA was necessary to evaluate potential Project Options to address the fish passage and other ecosystem issues. The New Brunswick Department of Supply and Services (NBDSS) were tasked with identifying a means to rectify these issues, and a harmonized federal-provincial EIA was established with the issuance of joint Guidelines. In November 2002, NBDSS contracted AMEC Earth and Environmental, a Division of AMEC Americas Ltd (AMEC) to undertake the EIA. AMEC led a Study Team that comprised experts from AMEC (project managers, engineers, biologists, public consultation facilitator) and experts (biologists, engineers, modellers, EIA practitioners, economists and social scientists) from other firms in Canada including: Jacques Whitford; ADI Limited; Canadian Hydraulics Centre; Gemtec Limited; GPI Atlantic (as recommended by the Niles Report); and Gardner Pinfold Consulting Economists Limited. Many of these experts had previously done work involving the Petitcodiac River, and some had up to 30 years of experience in this regard.

The EIA evaluated four Project Options recommended by the Niles Report that were intended to meet the Project Objectives and considered other relevant options identified during the EIA. The Project Objectives were to achieve a long-term solution to fish passage (i.e., achieve compliance with the intent of the original DFO requirement to provide a fishway at the causeway) and other ecosystem issues related to the causeway, including tidal exchange, sediment transport and other physical processes and biophysical functions (e.g., wetlands, populations of flora and fauna, fish habitat).

The principal purpose of the EIA was to evaluate and compare the potential environmental effects of the Project Options that meet the fish passage Project Objective (a long-term solution to fish passage; the unimpeded and safe movement, upstream or downstream, of fish between aquatic habitats required for their life cycle), determine if the selected Project Options also meet the other Project Objectives (i.e., ecosystem issues), analyze proposed mitigation and determine significance of the residual environmental effects and compare those to current conditions and the Status Quo (i.e., the current causeway conditions continued into the future). The fish species that were determined to require passage at the causeway were as follows: Atlantic tomcod, rainbow smelt, gaspereau (both alewife and blueback herring), brook trout, American shad, American eel, sea lamprey, Atlantic sturgeon and Atlantic salmon.

The EIA Report was the result of almost three years of research, consultation, modelling and analyses conducted by the AMEC Earth and Environmental Limited (AMEC) Study Team. The AMEC Study Team wrote the EIA Report on behalf of NBDSS. The EIA Report is intended to fulfill the reporting requirements for an Environmental Impact Assessment Report pursuant to the Clean Environment Act—Environmental Impact Assessment Regulation (EIA Regulation) and is the supporting document for the Screening Report (to be prepared by the Responsible Authorities) under the Canadian Environmental Assessment Act (CEAA). The EIA and EIA Report fulfill the requirements of the Guidelines for an Environmental Impact Assessment – Modifications to the Petitcodiac River Causeway (the “Guidelines”) issued on July 26, 2002 (New Brunswick Department of Environment and Local Government (NBDELG), 2002). The Guidelines reflected the Niles Report and a modelling workshop organized by Environment Canada and DFO in March 2002 to address the issues associated with modelling of the Petitcodiac River and identify the path forward for modelling the Petitcodiac River estuary in order to facilitate the EIA.

The Terms of Reference, prepared by NBDSS on how the EIA would meet the Guidelines, contained details for carrying out three Component Studies. The Component Studies were completed to provide the information necessary to support the EIA Report. The component studies were a Biophysical Component Study (AMEC, 2005a), a Socio-economic Component Study (AMEC, 2005a) and a Hydrodynamic and Sediment Transport Modelling Component Study (AMEC, 2005b).

The conduct of the EIA involved thorough consultation and communication with the public, stakeholders and regulatory authorities and meetings with the Aboriginal Community that was ongoing for the duration of the EIA. Issues not previously identified in the Guidelines were documented and addressed in the EIA Report. Thirteen Valued Environmental Components (VECs) were selected for the EIA, comprising a range of biophysical, socio-cultural and economic aspects of the environment that may be affected by the Status Quo and Project Options. These are as follows:
  • Atmospheric Environment;
  • Fish and Fish Habitat;
  • Terrestrial and Wetland Environments;
  • Municipal Services and Infrastructure;
  • Road Transportation Network;
  • Vessel Traffic and Navigation;
  • Land Use and Value;
  • Aboriginal Land and Resource Use;
  • Tourism;
  • Recreation;
  • Labour and Economy;
  • Heritage and Archaeological Resources; and
  • Public Health and Safety.

The Petitcodiac River estuary (Figure 1) is unique. The estuary is macro-tidal (i.e., with tides averaging 11 m) with an unparalleled suspended sediment loading typically in the order of up to 30,000 mg/L. The causeway (as shown in Figure 2) is located in the upper portion of the estuary, 20 km from the head of tide. There were very few similar examples found elsewhere in the world where fish passage facilities were incorporated in a facility that is located in a macro-tidal estuary and none display the combination of suspended sediments and macro-tidal conditions. The causeway also experiences temperature extremes from 30°C in the summer to –35°C in the winter. The physical nature of the estuary and the presence of the headpond and gates in the causeway, present challenges for the management of sedimentation and results in the potential for ice jamming and related operational issues. Consequently, a complex Gate Management Plan is in place to ensure safe operation of the facility, and in an effort to ensure improved opportunities for passage of some fish species. As stated previously, the Gate Management Plan has failed to meet the DFO requirement of the original intent of providing a fishway at the causeway.

The Project Options considered were:
  • Project Option 1—replacing the fishway;
  • Project Option 2—gates open during peak migration;
  • Project Option 3—gates open permanently; and
  • Project Option 4—replace the causeway with a partial bridge.

The Status Quo is the term recommended by Niles for continuation of the current gate management plan (i.e., no change) and has been considered in this report for comparison to the Project Options. The Status Quo was not considered as a Project Option as it does not and cannot meet the Project Objectives.

The existing fish passage issues were reviewed and found to include a number of impediments to fish passage. These included predation (birds and large fish eating smaller fish near the causeway), difficulties in negotiating the fishway, gate management, dissolved oxygen barriers, a seasonal sediment plug that extends several kilometres downstream of the causeway and upstream of the causeway, and a headpond water level elevation that is lower than highest tide providing insufficient attraction flow for fish.

An exhaustive evaluation of fisheries facilities in New Brunswick, Canada and elsewhere in the world was conducted to identify potential fishway solutions. It was evident that the issues associated with the causeway fish passage facility are difficult to overcome. Technologies that have been applied at other facilities were not applicable to the Petitcodiac River facility. This was mainly due to the unique characteristics of the Petitcodiac River (low and highly variable rate of freshwater flow, high tidal range and high suspended sediment concentrations) and the variety of fish species requiring migration. Examination of the facilities revealed that none examined could provide fish passage, upstream or downstream, for all of the fish species requiring passage at the causeway. It was therefore concluded that a new fishway or further enhancement to the gate management strategy would not be feasible to provide upstream and downstream passage for these fish species. Hence, Project Option 1 (replacing the fishway) would not meet the fish passage Project Objective of providing unimpeded and safe movement of fish upstream or downstream, between aquatic habitats required to complete their life cycle.

Peak fish migration occurs in the spring and fall, with a considerable upstream and downstream migration also occurring in the summer and winter. Opening the gates in the spring and fall only would not provide passage opportunities for all of the identified fish species requiring migration at the causeway and therefore Project Option 2 (gates open during peak migration) would not meet the fish passage Project Objective. Project Option 2 would also be burdened with other issues such as continued sediment accumulation in the headpond, ice-jamming at the gate piers in the winter months, and the summer and winter headpond would be brackish and unsuitable for freshwater fish species.

Project Options 3 (gates open permanently) and 4 (replace the causeway with a partial bridge) would both meet the fish passage Project Objective as they allow free tidal exchange and the movement of fish species that require passage.

Design Criteria for the Project Options were developed in addition to the main project objective of safe and unimpeded passage of fish so that these Project Options could meet the other Project Objectives (i.e., ecosystem issues) as well. These criteria included:
  • reversing the current infilling trend within the river both upstream and downstream of the causeway;
  • the protection of species regulated by SARA or the New Brunswick Endangered Species Act;
  • free passage of ice;
  • protection of wetland area that provides water quality treatment for the former Moncton Landfill immediately downstream of the causeway and the integrity of the landfill itself; and
  • design life of at least 100 years, including consideration of a sea level rise of 88 cm in the next 100 years.

Project Option 3 (gates open permanently) involves the removal of all gates and all but one pier at the location of the existing gates and provides an opening of 68 m wide.

Project Option 4 (replace the causeway with a partial bridge) has been split into the following three separate Project Options that were distinct ways of engineering a partial bridge:
  • Project Option 4A involves construction of a 170 m long bridge downstream of the existing gates and the removal of the entire gate and fishway structure to provide an opening of 72 m;
  • Project Option 4B involves a new bridge, 280 m long downstream of the existing gates that would afford a range of potential openings from 72 to 225 m; and
  • Project Option 4C involves a 280 m long, bridge in the central portion of the causeway, providing a river channel width of 225 m.

Mitigation strategies were built into the design of these Project Options so that the Design Criteria and other Project Objectives can be met. These strategies include erosion and scour protection along critical riverbank locations and the former Moncton Landfill between the causeway and Gunningsville Bridge. Compensation for affected facilities or operations (e.g., Sea Cadet, Tri Community Marina, Town of Riverview public dock) was included.

The following precautionary three-staged implementation strategy was developed for each Project Option:
  • Stage 1—Design, construction and communication prior to opening the existing gates;
  • Stage 2—Open existing gates; and
  • Stage 3—Construct the structure required for the preferred Project Option.

Stage 3 involves the following actions for each of the Project Options that meet the fish passage objective:
  • for Project Option 3, remove the piers and fish passage facility and replace/construct the bridge deck;
  • for Project Option 4A, construct a new bridge downstream of the causeway and remove the piers and fish passage facility;
  • for Project Option 4B, construct a new bridge downstream of the causeway and remove the control structure and a portion of the causeway (although this initially may be only removal of the control structure with subsequent removal of a portion of the causeway at a later date); and
  • for Project Option 4C, construct cofferdams and a temporary bypass, create an opening in the central portion of the causeway, construct a new bridge and then remove the cofferdams and temporary bypass to permit flow through the causeway. The control structure would be filled in.

This precautionary approach would ensure that the selected Project Option would be implemented successfully and that predictions made in the EIA Report would be verified through monitoring of the evolution of the channel before irreversible decisions could be made for the next stage.

Hydrodynamic and sediment transport computer modelling was one tool used to assist in predicting changes to the river. Trend analyses, interviews with people knowledgeable about the river (including government departments and agencies such as DFO) and the expertise of the AMEC Study Team, were also used to assist in describing the future anticipated changes to the River for each of the Project Options that met the fish passage Project Objective. Specifically this was Project Option 3 (gates open permanently) and Project Option 4 (replace the causeway with a partial bridge).

Under the Status Quo, the channel downstream of the causeway would continue to progressively infill. The tidal volume would continue to decrease. Equilibrium would not be anticipated to occur for another 70 years. It was anticipated that tidal elevations in the Moncton area would increase by about 0.2 m due to infilling. Flooding risk under open water conditions would increase under the Status Quo due to infilling both upstream and downstream of the causeway. Current problems with dissolved oxygen downstream of the causeway would continue and likely worsen with the Status Quo. Existing ice jamming and channel narrowing would continue and worsen under the Status Quo.

Project Options 3 and 4 (i.e., 4A, 4B, 4C) would reverse all of these problems identified for the Status Quo. Full tidal exchange would occur up to Salisbury, but the headpond would be lost. The channel would increase in width and depth and the tidal prism would increase, more for Project Option 4 than Project Option 3. Flooding risk would be reduced due to improved conveyance capacity (the amount of water that can move through the river in a given amount of time). Dissolved oxygen problems would be alleviated due to the increased dilution. Sediment removed from the river as the river widens and deepens will be transported to Shepody and Chignecto Bays, but held in suspension in those bays until ultimately transported into the central portion of Bay of Fundy. Opening the causeway would not result in an alteration of the lobster and scallop beds in Shepody and Chignecto Bays or an alteration of the conditions at Hopewell Rocks.

A comprehensive environmental effects assessment was conducted of the Project Options that met the fish passage Project Objective (Project Options 3 and 4) each of the 13 VECs. As noted above, the Status Quo was included for comparison purposes, and the effects assessment was also carried out for the Status Quo. The environmental effects were evaluated for each VEC including the required mitigation. Mitigation of the Status Quo was not described as it was not a Project Option and was provided for comparative purposes only. Table 1 summarizes the results of the environmental effects assessment showing whether or not the potential residual environmental effects were determined to be significant (S), not significant (NS) or positive (P). The Project Options 3, 4A, 4B and 4C did not have different overall conclusions and are therefore presented as one column in the table.

The Status Quo would not meet the Project Objectives and the Status Quo would result in significant negative environmental effects on most VECs, and no overall positive environmental effects on a VEC-by-VEC basis. These significant environmental effects were primarily related directly or indirectly to sedimentation and the loss of the tidal prism and channel conveyance. These significant environmental effects were those that have led to need for the EIA and to a large extent, determined the Project Objectives (i.e., restore fish passage and other ecosystem issues). The Status Quo would have some positive environmental effects (i.e., recreational smallmouth bass fishery and modest vacant land value enhancement adjacent to the headpond, float plane access on the headpond). These tend to lessen the significant negative environmental effects but clearly not to the extent that would render other negative environmental effects not significant, overall.

Overall, the Project Options would result in several positive environmental effects. Most importantly, these Project Options meet the fish passage Project Objective. Fish passage would be restored for the nine species that require passage through the consequent changes to the Petitcodiac River estuary. Other ecosystem issues (e.g., tidal exchange, sediment transport and other physical processes and biophysical functions) and socio-economic issues were similarly addressed. A summary of some of the key issues (i.e., change wetlands and mudflats, change in tourism opportunity, change in property value, change in need for additional sewage treatment) follows.

The Project Options would not result in a substantive interaction between the river and the abandoned City of Moncton Landfill located adjacent to the causeway. The modelling has clearly demonstrated that the new channel (i.e., after implementation of the Project Options) would not erode much of the extensive wetland currently in place between the landfill and the

Valued Environmental Component	Sub-component	Status Quo	Project Options
Atmospheric Environment	Climate Air Quality Odour Sound Quality	NS NS NS NS	NS NS NS NS-P
Fish and Fish Habitat	Sediment Quality Water Quality Fish/Aquatic Animal Species Fish Species at Risk Invasive Fish Species Fish Habitat	NS S S S S S	NS P NS-P P P NS-P
Terrestrial and Wetland Environment	Wetlands Wildlife and Vegetation Migratory Birds Mudflat Productivity Managed Areas	S NS P NS P	NS NS P NS NS
Municipal Services and Infrastructure	Water Distribution Systems Sanitary Sewer Systems Storm Sewer Systems Dykes and Aboiteaux Other Infrastructure	NS S S NS NS	NS NS-P NS-P NS NS
Road Transportation Network		S	NS-P
Vessel Traffic and Navigation		S	NS-P
Land Use and Value		S	NS-P
Current Use of Land and Resources for Traditional Purposes by Aboriginal Persons		S	P
Tourism		S	P
Recreation		S	P
Labour and Economy		S	NS-P
Heritage and Archaeological Resources		NS	NS
Public Health and Safety	Vehicular Accidents Non-vehicular Accidents and Unplanned Events Groundwater Quality and Quantity Contaminated Effluents and Redistribution of Contaminants Human Disease Vectors Flooding	NS NS NS S NS S	NS NS NS NS-P P P
S = Significant, NS = Not Significant, P = Positive

river channel. Regardless, as a precautionary measure, it is recommended that erosion protection measures (riprap for all Project Options and sheet piling for Project Options 4B and 4C) be put in place around the landfill to prevent any unanticipated interactions between the river and the landfill from occurring.

The Project Options would not result in substantive environmental effects on lobster or scallop or their habitat. It was concluded that there is no scientific basis for a correlation between the installation of the causeway and the coincidental increase in lobster and scallop populations in the Shepody and Chignecto Bays. Also, a thorough review of the most recent studies regarding sediment distribution processes in Shepody and Chignecto Bays suggests that most of the sediment that would be released from the Petitcodiac River, with implementation of the Project Options, would be deposited in the Bay of Fundy, and would not accumulate in Shepody or Chignecto Bays.

The Project Options would result in positive environmental effects on wetlands and mudflats. Although the Project Options will cause the overall loss of wetland area, the restoration of estuarine conditions in the area above the causeway will expand the current distribution of provincially significant saltwater marsh, and the increased flushing action downstream of the causeway will enhance saltwater marsh productivity in that area. Similarly, mudflat productivity will be more like what existed in pre-causeway times. Of most importance, the mudshrimp (an important food for migratory birds) requires estuarine or saline conditions. The Project Options will therefore extend the current distribution of mudshrimp to include the mudflats above Dover (the current edge of distribution), including the mudflats above the causeway.

The Project Options would result in positive environmental effects on tourism opportunity along the Petitcodiac River. Most notably, the Project Options would result in the enhancement of the tidal bore. Although it was not considered likely that the tidal bore would attain pre-causeway size, it would be larger and more consistent throughout the year. Implementation of the Project Options may reduce channel infilling near Hopewell Cape, but would not affect the Hopewell Rocks.

The Project Options would also result in adverse environmental effects on recreation opportunity. Alteration of the headpond would, without mitigation, affect the activities of the Tri Community Marina, Town of Riverview public boat launch, the Sea Cadet training facility, float planes and private docks, and would result in the loss of the smallmouth bass and chain pickerel fishery between the causeway and Salisbury. However, the overall environmental effects are anticipated to be positive as opportunity to pursue native fish species such as striped bass, American shad, sea-run brook trout and possibly Atlantic salmon (should this species eventually recover and be removed from the Species at Risk Act) will improve, and the removal of the causeway as an obstruction to navigation and the free tidal exchange in a deeper and wider channel will afford greatly enhanced opportunity for river-based recreation.

The Project Options would result in negative, but not significant, changes in the value of some types of property. Specifically, the Project Options may potentially result in a decrease (-5%) in value of vacant land property immediately adjacent to the headpond (i.e., on the waterfront and above the causeway). The Project Options would not likely result in a significant change in value to developed waterfront property anywhere along the Petitcodiac River.

The Project Options would result in an improved assimilative capacity (the ability of the river to accept wastewater while maintaining acceptable water quality) of the river due to the increased tidal prism and the subsequent improvement to dissolved oxygen levels. As a consequence, the need for additional sewage treatment facilities at Outhouse Point that exists under the Status Quo is greatly reduced, possibly eliminated. However, additional sewage treatment may be necessary in the future as a result of changes in environmental legislation and increased population. In this case, the Project Options will defer the need for additional sewage treatment facilities at Outhouse Point.

The Project Options would result in some negative environmental effects that would not be significant due to their limited magnitude, extent, duration, frequency and/or reversibility and in consideration of planned mitigation. Key mitigation includes shoreline erosion protection downstream of the causeway, embankment protection at the former Moncton Landfill immediately downstream of the causeway, protection of the riverbank along the Riverview walking trails, restoration and maintenance of agricultural dykes and aboiteaux above the headpond, and compensation for loss of the Tri Community Marina. The Project Options included a comprehensive environmental management strategy that would ensure sound design, construction and operational practices, and an adaptive management approach based on a precautionary implementation strategy and the associated Follow-up Program.

The aspects of the environment that may cause a change in the design or construction of the Project Options and the Status Quo considered in the EIA Report included the following: sediment transport process; tidal prism; weather; flooding; ice; climate change and earthquake activity.

Good engineering planning and design always involves consideration of effects of the environment on a project and the planning and engineering design for the Project Options (3, 4A, 4B and 4C) were no exception. The mitigation (e.g., riprap of erodible shorelines) for potential effects of the environment on the Project were inherent in the planning and engineering design as presented in this EIA Report. In addition, Stage 1 of the Project Options implementation plan would further define the mitigation for construction and operation of the Project Options and monitoring and follow-up, as described in Chapter 12, would further minimize the likelihood of a substantive effect of the environment on the Project Options from occurring.

In consideration of the likely effects of the environment on the Project Options and the proposed mitigation (including monitoring and follow-up), the residual effects of the environment on the Project Options were determined to be not significant.

By contrast, the Status Quo would continue to result in a changing environment due to sedimentation and reduction in tidal exchange. This would in some instances result in an effect of the environment on the Status Quo that would be significant (e.g., increased flooding risk due to decline in channel conveyance, made worse by relative sea level risemade worse due in part to climate change).

The assessment of cumulative environmental effects expanded on the environmental effects analysis of the Status Quo and Project Options (3, 4A, 4B and 4C). Once established, the environmental effects of the Status Quo and Project Options must overlap with those of other past, present and future actions for a cumulative environmental effect to result. The environmental effects assessment and analysis of the effects of the environment on the Status Quo and Project Options very thoroughly established the cumulative environmental effects of past and present actions, including the contribution of the causeway to date. The cumulative environmental effects of the Status Quo and Project Options were evaluated in respect of four main categories of future actions: global, land use, economic and cultural.

Evaluation of these cumulative environmental effects demonstrated that the cumulative environmental effects of past, present and future actions that overlap with those of the Status Quo and Project Options were consistent with those identified in the environmental effects assessment and assessment of the effects of the environment of project. Future actions including other future development projects (e.g., City of Moncton Assomption Boulevard Phase II and Vaughan Harvey Boulevard Extensions) would not contribute in substantive ways to cumulative environmental effects.

Importantly, the Status Quo contributed substantively to cumulative environmental effects that were determined to be significant and negative. These included the persistence of Fish and Fish Habitat issues (i.e., not meeting the fish passage Project Objective), and also:
  • sedimentation and ice blocking outfall flapgates and drainage ditches downstream of the causeway;
  • increased flooding of roads;
  • sedimentation further reduces navigability;
  • increased flooding would result in property damage and increased insurance premiums;
  • the loss of opportunity for land and resource use for traditional purposes by the Aboriginal Community;
  • the loss of a natural estuary and the tidal bore and related tourism opportunity;
  • the loss of some recreational fisheries;
  • the loss or reduction of some commercial fisheries (e.g., American shad); and
  • increased flooding risk and public safety and human health risk due to recreational contact.

By contrast in meeting the Project Objectives, the Project Options would contribute to positive cumulative environmental effects due to changes to the Petitcodiac River estuary that afford the restoration of fish passage and the overall ecosystem benefits (tidal exchange, sediment transport and other physical processes and biophysical functions). Mitigation planned for the Project Options would mitigate potential cumulative environmental effects and no specific mitigation would be required to address cumulative environmental effects beyond those measures.

A Follow-up Program would be implemented to meet the requirements of both the Guidelines and CEAA, and would be consistent with the implementation strategy for each Project Option. The overall objective of the Follow-up Program would be to support the successful implementation for the selected Project Option so that it meets the Project Objectives.

In Stage I of the precautionary implementation strategy, the Follow-up Program would focus on the collection of baseline data (if required and not already available) to be used as a benchmark for follow-up of the environmental effects assessment predictions. Data collection would include cross- sections of the upstream channel excavation, tourist surveys in the GMA, and the assembly of catch data for commercial lobster, scallop and eel fisheries.

In Stage II of the precautionary implementation strategy, the Follow-up Program would verify the accuracy of short-term modelling predictions of changes to the river channel, through the seasonal measurement of cross sections along the length of the river. Follow-up would also verify the effectiveness of mitigation measures implemented in Stage I before the gates were opened (i.e., upstream dyke restoration, former Moncton Landfill erosion protection, watermain relocation, embankment and channel bottom protection, and channel excavation upstream of causeway to facilitate initiation of the erosion process). Tourism surveys and commercial fisheries catch data would continue to be collected/assembled throughout Stage II.

In Stage III of the precautionary implementation strategy, the Follow-up Program would verify the effectiveness of mitigation measures and the accuracy of environmental effects assessment and modelling predictions. Follow-up would focus on physical characteristics of the Petitcodiac River estuary as they relate to the following VECs: Fish and Fish Habitat, Terrestrial and Wetland Environment, Municipal Services and Infrastructure, Vessel Traffic and Navigation, Tourism, Labour and Economy, Heritage and Archaeological Resources and Public Health and Safety. In addition, the Follow-up Program would include: collection of sediment and water quality data; air photo interpretation to determine changes in wetland and mudflat areas; evaluation of river-front property market values; continued communication with the Aboriginal Community; collection of river-based tourism, boating and angling survey data; inspection of trails adjacent to the river; continued assembly of commercial fisheries data; evaluation of boater stranding statistics and forest fire fighting resources; and visual inspection of mitigation measures (i.e., watermain relocation, upstream dyke restoration, former Moncton Landfill erosion protection and embankment protection).

The Follow-up Program would focus on an adaptive management approach to verify the conclusions and the effectiveness of mitigation, and in the unlikely event of unanticipated changes to the river or failure of mitigation measures, be used to update the EMP before each construction stage would be implemented.

The benefits and costs of the causeway to date, and out into the future with the Status Quo and Project Options (3, 4A, 4B and 4C) that met the Project Objectives were considered. Capital and operating costs were characterized for the Status Quo and Project Options. Other economic considerations associated with the causeway to date (i.e., intangibles or benefits and costs that were difficult to attach “hard costs” to), Status Quo and Project Options were qualitatively and, where feasible, quantitatively analyzed.

On the whole, it was concluded that the costs of the causeway have, from a benefit and cost perspective, not been favorable. This is particularly true when one considers the fact that these negative significant environmental effects would not have occurred if a bridge had been constructed rather than a causeway, although maintenance and possibly enhancement of agricultural dykes and aboiteaux upstream of the causeway would have been required.

The original causeway construction cost between $18,000,000 and $24,000,000 in 2004 dollars. Similar costs would have been expended to build a bridge. The capital and operating cost of the Status Quo going forward from 2005 would be on the surface relatively small for maintenance and operation of the gates, and occasional major repairs (i.e., $666,800 every 15 years). What was not factored into the Status Quo was the undefined but substantial costs associated with elevated flood risk that would result in increased magnitude and frequency of flooding, and/or increased insurance rates (likely in the tens of millions of dollars).

It was estimated that the cost of sewage treatment improvements to address current water quality issues alone would be in the order of $36,400,000. As such, the direct and indirect costs of the Status Quo in future would be well in excess of $36,400,000. However, due to anticipated changes in regulatory requirements for municipal wastewater, it would be possible that at some time in the future improved treatment may be required at the GMSC wastewater treatment facility regardless of the presence or absence of the causeway. If this were to occur, then the direct costs of improvement (estimated at $36,400,000) would not be attributable to the Status Quo, but could at least be deferred to some future time.

The capital and operating cost of the Project Options is summarized in Table 2.

Table 2 Capital and Operating Costs of the Project Options*
Activity	Project Option 3	Project Option 4A	Project Option 4B	Project Option 4C
Sub-total Stage 1	$18,430,000	$20,390,000	$20,390,000	$21,610,000
Sub-total Stage 2	$3,120,000	$3,960,000	$5,080,000	$7,000,000
Sub-total Stage 3	$12,530,000	$17,600,000	$29,140,000	$78,660,000
Total Costs	$34,080,000	$41,950,000	$54,610,000	$107,270,000
*all values in 2004 CDN dollars and include 25% contingency (see Table 12.2.1 for detail)

The costs of Project Options 4B and 4C would likely be fully or almost entirely offset by future avoided costs of the Status Quo when the avoided cost of flood protection, damage, or property insurance were factored in, along with other identified costs. These costs may be further alleviated by the deferred or avoided costs of sewage treatment upgrades.

The Status Quo on the whole has many costs associated with the predicted significant negative environmental effects, but in addition, there could be the consequences of ongoing violation of Section 20 of the Fisheries Act and future violation of Section 33 of the Species At Risk Act (Atlantic salmon and dwarf wedgemussel) that were not quantified as part of this study, but may result in additional costs (e.g., fines). Conversely, the Project Options in meeting the Project Objectives would overall result in many benefits that on the whole would result in even greater net benefits (e.g., tourism, commercial and recreational fishing and navigation).

From a full cost accounting perspective, notwithstanding regulatory considerations, it would appear that the costs of implementing Project Options, in effect, would be largely nullified, through the benefits that would be accrued (e.g., reduced flood risk, tourism, commercial and recreational fishing and navigation) and the avoided future costs of the Status Quo (e.g., flood protection, damage and insurance).

For fish passage to be re-established on the Petitcodiac River for nine important species, the Status Quo and Project Option 1 (replacing the fishway) and Project Option 2 (gates open during peak migration) will not achieve this. Only Project Option 3 (gates open permanently) and Project Option 4 (replace the causeway with a partial bridge) with modifications do.

Option 3 would be the least costly to build and operate, but would not have the enhanced benefits (increased sediment erosion and tidal exchange) of Project Option 4(A-C).

Project Option 4A is another way of achieving the same result as Project Option 3, but will have less of an environmental effect on traffic patterns during the construction phase.

Project Option 4B affords a greater degree of flexibility should predicted sediment erosion and increased tidal exchange be found to be less than predicted under Project Options 3 or 4A. Project Option 4B can start with just opening the control structure and, later, widen the causeway beyond the control structure if the tidal exchange needs to be enhanced. If this is not required, then the additional cost of widening the opening can be avoided.

Project Option 4C would be the most costly Project Option and would have inherent construction risks (dredging or cofferdam failure and proximity to the former Moncton Landfill immediately downstream) that would be much greater than the other Project Options.

From a full cost accounting perspective, notwithstanding regulatory considerations, it would appear that the costs of implementing Project Options, in effect, would be largely nullified, through the benefits that would be accrued (e.g., reduced flood risk, tourism, commercial and recreational fishing and navigation) and the avoided future costs of the Status Quo (e.g., flood protection, damage and insurance).