WORK PLAN SUMMARY
Consulting Services
Watershed Study Fall River Shubenacadie Lakes
HALIFAX REGIONAL MUNICIPALITY
PROJECTY NO. 1025549

1.0 INTRODUCTION

1.1 Background
The Fall River - Shubenacadie Lakes Watershed Study is one of a series of watershed studies mandated by the new HRM Regional Plan (August, 2006). Recognizing that “environmental features within a watershed all are connected and land-use activities in one part of the watershed can adversely affect quality and quantity of water in another”, the Regional Plan (Policy E-17) requires that watershed or sub-watershed studies are carried out as part of a comprehensive secondary planning process in various neighbourhoods within HRM. The ultimate goal of the watershed studies is to identify those lands most suitable for development through a land capacity analysis and provide specific watershed-appropriate guidelines for the planning and design of new developments and growth boundaries to balance development with environmental protection.
The Shubenacadie River Basin extends across central Nova Scotia from the Atlantic coastline to the Fundy Shore. The basin is composed of three main watersheds; the headwaters, the Shubenacadie River and the Stewiacke River. The study area is focused in the headwaters of the Shubenacadie River system where the Grand Lake watershed is found.
Over the past two decades the area has experienced dramatic expansion of development, infrastructure and services, and continued growth expected. Fall River, in particular, has expanded rapidly in the past decade as a suburban centre with the introduction of large scale retail developments and new residential subdivisions and schools. The Regional Plan delineates the Fall River as a Rural Commuter District Centre, with the primary intention of focusing low and medium-density development around a node or centre that is within easy commuting distance from the Regional Centre (downtown Halifax and Dartmouth). By focusing growth in a District Centre the Regional Plan aims to protect the character of this rural community, while conserving natural resources and open spaces. To facilitate the desired growth patterns and to balance growth with the sustained protection of water resources, the future provision and expansion of municipal wastewater and water distribution services may be considered.
The greater Shubenacadie-Grand Lake Watershed offers excellent development potential due to its central location on major transportation routes and its proximity to urban Halifax. The area is supported by a rich ecology with thousands of hectares of old growth forest, freshwater lakes and watercourses. The area contains some of the most productive land fringing on urban Halifax, however most of the land in the region is privately owned and open for development. It has been recognized that water quality in the area is vulnerable to the affects of suburban development and water quality declines have been documented over the past thirty years (Mudroch et al, 1987; Vaughan Engineering, 1993; Centre for Water Resource Studies, 1991).
The malfunction of on-site sewage systems and the need for centralized servicing were identified as key issues for water quality management, as well as mining wastes, natural geology, road salt and erosion. An integrated study of pollution control was commissioned in 1991 by a multi-stakeholder Task Force to address the issues. Phase I was completed in 1991 by Scott, Hart and Waller of the Centre for Water Resource Studies (key team members for the proposed work) to examine water quality in the lakes and model development scenarios to predict the impact to water resources. Phase II was completed by Vaughan Engineering with the intention of building upon the recommendations and conclusions of Phase I to recommend management strategies for lake water quality and measures to reduce existing contaminant loadings and minimize future inputs. This study proposes to build upon these past initiatives to assess the constraints and opportunities for development in the watershed in line with the new Regional Planning Strategy initiatives for the completion of watershed studies for areas designated as growth centres.
The 25-year Regional Planning Strategy for HRM puts in place a number of initiatives to protect the natural environment and in particular the health of HRM’s water resources: The Open Space and Natural Resource land use designation serves many functions including retention of flood waters; the establishment of a Protected Water Supply Zone protects the public potable water supply; the Wetland Protection Schedule paves the way forward for protection of key wetland functions such as absorbing peak stormwater flows, reducing flooding risks, and offsetting groundwater extraction. Riparian buffers and floodplains are both protected through by-laws, while the risk of coastal inundation is mitigated through residential set backs from the high water mark. The Water Quality Monitoring Function Plan, the Open Space Functional Plan and the Urban Forest Function Plan also play key roles in managing water resources sustainably.

1.2 Objectives and Scope of the Project

The overall objective of the project is to develop a strategy for land development in the Grand Lake – Shubenacadie Watershed and the Fall River Growth Centre to support the maintenance of water quality for a wide range of uses. The scope of this project is evaluate the capacity of the groundwater, receiving waters and ecological resources within the Shubenacadie – Grand Lake watershed to sustain development and growth and to assess options for servicing the Fall River Growth Area with central water and sewer.

2.0 APPROACH AND WORK PLAN

2.1 Approach
There are two key phases to the project; the first is to assess options for servicing the Fall River Growth Area with central water and sewer (Phase I) and the second is to address the management of the watershed as a whole by building upon previous detailed studies (Phase II).

Phase I Objectives

i. Determine capacities of existing sewage treatment plants, and establish residual capacity for growth or possibility for increase in capacity.
ii. Identify options for on-site and cluster treatment for providing sewage service to potential growth areas.
iii. Develop constraints and opportunities for central water distribution for unserviced areas.
iv. Assess condition of on-site septic systems, and recommend upgrade requirements for continued use in combination with a central water supply.
Phase 2 Objectives
v. Develop receiving water quality objectives (RWQOs) for potential receiving water bodies within the study area;
vi. Determine the capacity of watershed receiving waters to meet the established RWQOs under existing and future predicted contaminant inputs;
vii. Determine the capacity and constraints of groundwater supply development and identify the potential risks to groundwater resources;
viii. Assess and provide recommendations for the protection of key ecological resources;
ix. Identify areas of particular sensitivity to development and recommend additional protective measures
x. Identify and prioritize areas that are suitable and not suitable for development within the watershed based on the specific environmental conditions of the watershed.
xi. Recommend options for regulatory controls and management strategies to guide development, environmental protection and land use practices in the watershed;
xii. Recommend strategies to adapt HRM’s stormwater management guidelines to achieve the RWQOs
xiii. Complete a water quality testing program of representative lakes, watercourses, and fish tissues for a variety of parameters to be incorporated into ongoing monitoring studys, to fill data gaps and it confirm identified risks
xiv. Propose a future monitoring program to confirm the goals of sustainable watershed development are being met

2.2 Work Plan
The project will require the integration of a number of specialized studies to produce a workable plan for watershed development and the protection of key resources. It will be completed as a series of objective-based tasks to further facilitate integration of the studies to produce a comprehensive and logical report for ease of use in watershed management, as described below.

2.2.1 Determine capacities of existing sewage treatment plants, and establish residual capacity for growth or possibility for increase in capacity (PHASE 1)
The purpose of the Phase I study is to look at options for servicing Fall River Rural Commuter area with both central water and sewer. Land use studies have indicated that the Fall River area has the land mass to support growth in an area in proximity to urban Halifax on a major transportation route (a targeted population increase of 2000 residents). On site sewer and individual private water wells are not suited to these conditions due to well interactions and progressive aquifer drawdown and the capacity of the subsurface to attenuate bacteria and nutrient inputs from the density of septic beds. An efficient central water and wastewater system is desired to facilitate the growth of the medium density community and protect receiving waters from long term degradation. This study will assess the capacity for expansion of existing servicing and options for further servicing will be provided.

2.2.2 Identify options for on-site and cluster treatment for providing sewage service to potential growth areas (PHASE 1)
Options for sewage treatment and disposal will be reviewed for the unserviced areas, including individual on-site, cluster with land dispersal, and central collection and small scale central treatment. Advantages and disadvantages of the options, as well as compatibility of different collection systems (STEP, small diameter gravity sewer, vacuum and pressure sewers, etc.) with the proposed treatment systems will be discussed.

2.2.3 Develop constraints and opportunities for central water distribution for unserviced areas (PHASE 1)
The study team will obtain and review the computer model from HRWC for the subject area, and identify the output nodes which will form the basis for the inputs into the “mini model” for the Fall River Sub-study Area. We will conduct the WaterCAD computer model to “map” available flow rates and pressure zones and to determine constraints and opportunities for central water distribution. Based on the results of this computer modeling and analysis, we will identify development scenarios.

2.2.4 Assess condition of on-site septic systems, and recommend upgrade requirements for continued use in combination with a central water supply (PHASE 1)
A high-level assessment of existing on-site septic systems will be conducted to determine the magnitude of impact from provision of central water distribution to this area. Based on information from NSDEL and other sources, we propose to establish the existing degree of system failures, and estimate the increase in failure rates resulting from extension of the water system. Also, we will assess the positive impact of providing central or alternate treatment systems in alleviating existing pollution from existing failed systems.
Based on the findings of the septic system assessment, the study team will develop options for upgrading or replacement of existing septic systems. Options will include extension of contour system trench, replacement with individual or cluster mounds or area beds, use of recirculating sand filter as pre-treatment to percolation into the soil, peat systems, etc.

2.2.5 Develop receiving water quality objectives (RWQOs) for potential

receiving water bodies within the study area
The Receiving Waters Team will analyse available water quality data from previous studies as well as the results of the monitoring program to determine the present status of the headwaters and the potential for further additions of phosphorus. Assimilative capacity and water quality objectives can be predicted using the CCME Framework for Phosphorus management, historical data.

2.2.6 Determine the capacity of watershed receiving waters to meet the established RWQOs under existing and future predicted contaminant inputs
Using historical and present day data the Receiving Waters Team will develop a phosphorus loading model to determine present trophic status and future status based on servicing options provided in Phase I and predicted populations and land use data provided by HRM. Estimates of current annual sediment loading to receiving lakes and rivers will be developed using USLE based modeling approach.

2.2.7 Determine the capacity and constraints of groundwater supply development and identify the potential risks to groundwater resources (PHASE 2)
The Groundwater Resources team will characterize the groundwater development potential within the Shubenacadie Lakes Watershed to identify potential risks to groundwater resources. Outcomes will include:
? an understanding of the existing hydrogeology and groundwater resources,
? identification of constraints with respect to the development and protection of groundwater quality and quantity in the watershed,
? identification of the current risks to groundwater in the watershed, and
? recommendations for areas of preferred development based on the safety, quality and quantity of groundwater resources available.
The outcome will be a comprehensive groundwater monitoring strategy for the areas of concern. This would likely include a combination of monitoring wells with automated water level and water quality monitoring instrumentation.

2.2.8 Assess and provide recommendations for the protection of key ecological resources (PHASE 2)
Although the Shubenacadie–Grand Lake Watershed is home to the most productive land on the fringes of urban Halifax, forest and wetland habitats are declining and rich aquatic systems are eutrophying as a result of suburban sprawl. The Ecological Resources Team proposes to work with key local groups to identify valued ecological features in the watershed. Focussing first on the lands identified as having potential for a Wilderness Area, the important ecological resources will be identified, such as;
? Ecosystems known to support species at risk or locally important species (for example, salmon);
? Wetland inventory;
? Ecosystems or tracts of public and undeveloped land used for ecologically oriented recreation (bird watching, hiking, wildlife appreciation, canoeing, etc); and
? Pristine areas supporting high biodiversity.

Once key ecological resources are identified, experienced ecologists will employ a risk management approach using available land use mapping and development plans provided by HRM to identify existing and future pressures to these valued ecosystems, the key sensitivities of these systems, and opportunities to protect them. Ecological information will also inform the process to develop site-specific riparian and coastal buffers for the protection of the water resources.

2.2.9 Buffer Zones: Identify areas of particular sensitivity to development and recommend additional protective measures (PHASE 2)
During the course of the watershed resource studies, certain areas will be identified that are particularly valued or sensitive to the effects of development. These areas may include but not be limited to;
? Groundwater recharge areas;
? Wetland habitats;
? Portions of receiving water catchments that contribute significantly to water quality in a surface water supply;
? Habitats supporting species of concern or local value;
? Important natural corridors to allow wildlife migration and ecosystem connectivity;
? First order watercourse headwaters;
? Areas with little ability to attenuate contaminant inputs, such as areas with bedrock at or near surface with little or no natural surface cover; or
? Areas of concentrated private water supply wells.

Site specific recommendations will be provided by each of the study teams to address these key concerns through methods such as increasing the minimum riparian buffer zone requirements in specific stretches of a watercourse (standard is 20 m); recommending a gradual replacement of impermeable surface in key areas; grandfathering out certain landuses in key areas (i.e, restrictions on the establishment of new chemical and fuel handling facilities such as gas stations in well capture zones).

2.2.10 Identify and prioritize areas that are suitable and not suitable for development within the watershed based on the specific environmental conditions of the watershed (PHASE 2)
The outcomes of the detailed watershed resource studies described above will include an identification of the constraints and opportunities for development related to the preservation of each of the valued watershed resources. The key development constraint and opportunities maps produced for each resource (groundwater, receiving waters, habitat, etc) will be integrated into a GIS model. Each layer of data will represent a constraint (e.g., riparian zone) or an opportunity (e.g., land that is hydrologically disconnected from sensitive receiving waters and groundwater supplies) for development.

2.2.11 Recommend options for regulatory controls and management strategies to guide development, environmental protection and land use practices in the watershed (PHASE 2)
HRM has at its disposal a number of planning and land use management tools which can be used to guide the extent, type and impact of development within the watershed. These will be evaluated by the project team and recommendations made with regard to the best approach.

2.2.12 Recommend Strategies to adapt HRM’s Stormwater Management Guidelines to Achieve the RWQOs (PHASE 2)
HRM’s Stormwater Management Guidelines were developed in 2006 to identify Best Management Practices (BMPs), techniques and methods of managing stormwater drainage for the protection of the environment. The guidelines offer general design criteria that should be used in HRM for quantity, quality, erosion, and base flow control. The intended use of the guidelines is to be adapted and applied on a watershed specific basis, according to the locally unique characteristics and sensitivities. The Stormwater Management Team will identify sensitive features requiring additional protection, key source areas for water-laden contaminants (salt, metals, petroleum hydrocarbons, sediment), and areas suitable for development. The Team will recommend specific BMPs for stormwater management that may be implemented to suit the conditions of the watershed.

2.2.13 Complete a water quality testing program of representative lakes, watercourses, and fish tissues for a variety of parameters to be incorporated into ongoing monitoring studies, to fill data gaps and confirm identified risks (PHASE 2)
HRM is currently undertaking bi-annual limnological surveys of over 50 lakes within the municipality, including three lakes within the Grand Lake/Shubenacadie Watershed. Surveys are also conducted on 63 HRM lakes that focus on monitoring fecal coliform levels at lake outlets. To assess the trophic status of the major lakes in the watershed and recommend water quality objectives for the region, the Recieving Waters Study Team will build upon HRM’s existing programs. To complement the existing surveys conducted on Lake Thomas, Lake William and Lake Charles, detailed hydrographic profiles and water quality assessments surveys of the deep basins of Grand and Fletcher lakes will be conducted in the spring and summer. Other selected lakes will be sampled to supplement the understanding of surface water quality in the watershed. The lakes and analysed parameters will be selected to fill specific data gaps identified during the existing conditions reviews conducted by each of the Study Teams, and to confirm identified contaminant risks.
HRM proposes to obtain an update on the status of bioaccumulation of heavy metals such as mercury in the watershed under this statement of work. The Receiving Waters Study Team will complete a fish tissue sampling and analysis from lakes within the Shubenacadie-Grand Lake Watershed to determine mercury levels in tissue.

2.2.14 Propose a future monitoring program to confirm the goals of sustainable watershed development are being met (PHASE 2)
A monitoring plan will be proposed to reflect the learnings of the detailed watershed studies. The plan may include recommendations for monitoring of surface water bodies and groundwater, as relevant.

3.0 SCHEDULE
The project will be completed over the course of approximately seven months. A schedule of work is presented in Table 1 below.