Surface Water Management Programs
The overall goal of surface water management programs is to protect surface waters and ensure sustainable use for all beneficial uses. Beneficial uses include drinking water supplies, habitat for aquatic life, recreational use, agricultural and industrial uses. Sustainable use of water resources supports economic development, health of humans and aquatic ecosystems, overall environmental protection, and a high quality of life for Nova Scotians.
In order to properly manage surface water, it is necessary to;
- establish water resource inventories for both surface water quality and quantity,
- allocate available water resources amongst various users (through an approvals process),
- protect surface waters from human impacts through regulatory measures (e.g. approvals, regulations, guidelines, standards, policies), and non-regulatory or voluntary measures (e.g. promotion of watershed planning & best management practices (BMPs)),
- monitor surface waters to track trends in water quality and quantity,
- evaluate effectiveness of management programs.
The Department is involved in five primary areas to implement these key surface water management steps;
- Inventory
- Allocation
- Protection / Watershed Management
- Monitoring & Reporting
- Supporting Resource Management Tools & Evaluation
1. Surface Water Inventory
An inventory of surface water quality and quantity is necessary to assess capacity to accept potential changes as a result of human interventions or activities (eg water withdrawal or effluent discharge). It also allows evaluation of whether these activities and management decisions have been protective of the resource and are sustainable, using subsequent monitoring activities.
Surface water resource inventories were initiated in the 1960's resulting in a series of Water Resource Reports. More information can be found under Surface Water Monitoring & Reporting on this page.
2. Surface Water Allocation
Fair allocation of water resources to water users is a responsibility of the department which is delivered through its Water Approval process. An approval is required for withdrawals of water greater than 23,000 liters /day (Activities Designation Regulations). Allocation is intended to ensure sustainable use including protection of other water users and maintenance of fish habitat. The Water Resources Protection Act (2000) is also in place to address proposals for large scale bulk removals of water from the province.
Surface water withdrawal approvals allow the department to assess the potential effects of each proposed withdrawal on a case-by-case basis and track how much water has been allocated in watersheds across the province. In some cases, a hydrological study must be completed to evaluate the potential effects of the proposed withdrawal on existing surface water users and the environment. The evaluation includes an assessment of the following: sustainable flows / levels of the lake or stream, water quality effects, maintenance of flows for fish and other aquatic life habitat, and the potential for impacts on other water withdrawals and/or water users.
3. Surface Water Protection (Watershed Management)
The goal of surface water protection is to protect water quality by minimizing contamination of the resource from the surrounding watershed. The department works with municipalities and stakeholders to protect surface waters from various watershed influences through watershed management planning and the use of best management practices (BMPs). In watersheds where municipalities rely on surface water sources for drinking water, the development of Source Water Protection Plans is a requirement of NSEL approvals. A series of guidance documents exists to assist municipalities and landowners in protecting public water supplies. The documents can also serve to protect surface waters for other beneficial water uses - such as aquatic life habitat, recreational , and agricultural uses. To protect a surface water supply, the area that contributes water to the surface water body needs to be delineated so that potential sources of contamination can be identified and managed. This is described in Step 2 of the department’s “Guide to Developing a Municipal Source Water Protection Plan”. Step 3 outlines how to identify potential sources of contamination while Step 4 identifies options for managing contaminant sources. The following guidance documents are also available from the Watershed Planners in the Water and Wastewater Branch to assist municipalities or other stakeholders with the best management practices option presented in the Step 4 booklet:
- A Guide to Recommended Agricultural Practices within Municipal Drinking Water Supply Areas in Nova Scotia [link - DW website]
- Best Management Practices/Forest Planning in Municipal Drinking Water Supply Areas in Nova Scotia [link - DW website]
- Mineral Exploration and Development in Municipal Water Supply Areas [link - DW website]
4. Surface Water Monitoring & Reporting
The department's water monitoring programs are used to track long-term trends in surface water quality and quantity and to assess the effectiveness of water resource management programs. Monitoring programs are an essential tool for checking on the status of the province's surface water, assessing the impact of human activities on this resource, and evaluating long-term surface water trends associated with issues such as acid rain, eutrophication, and climate change.
The department's key surface water monitoring programs are: the Canada/Nova Scotia Hydrometric Network (archived data for stream flows), the Nova Scotia Lake Survey Program which inventories lake water chemistry and lake morphometrics (such as depth, volume, and stratification), and the Automated Surface Water Quality Monitoring Program which tracks water quality on an hourly basis at 5 locations in the province.
Other surface water monitoring programs which the department participates in include;
The department supports various volunteer and municipal water quality monitoring groups including:
- Kings County Volunteer Lake Monitoring Program
- CARP - Annapolis River Guardians Program
- Metro Area Lake Study
5. Surface Water Management Supporting Tools & Evaluation
An important component of the overall management of surface waters is the development and use of predictive, evaluatory, and interpretive tools. These include guidelines which establish limits for toxic substances in the ambient environment for the protection of various water uses [e.g., CCME Canadian Environmental Quality Guidelines (CEQG)]. These guidelines are used to help interpret water quality results from monitoring programs to assess whether water uses are supported or compromised. Other tools include predictive tools such as a phosphorus loading model which predicts effects of nutrient discharges and helps manage activities having nutrient rich discharges (see User’s Manual for Prediction of Phosphorus Concentrations in NS Lakes: A Tool for Decision Making version 1.0 (PDF: 1.5mb)). Another tool which can be used to help communicate water quality results is the Canadian Water Quality Index as has been developed through CCME with departmental staff participation. See the report entitled "Application and Testing of the Water Quality Index in Atlantic Canada (PDF)" for more information on testing in Atlantic Canada. This Water Quality Index has been used recently to communicate water quality monitoring results through the Canadian Environmental Sustainability Indicators (CESI) report.
Additionally, surface water related databases, GIS, maps and publications are useful tools for managing these resources, completing surface water investigations, and for responding to surface water related inquiries.
