Township of Langley: Stream Mapping for Better Local Water Resources Management

The Township of Langley initiated detailed mapping of streams and fish habitat in 1993. The stream survey data has been integrated into the Township’s GIS, and watercourse classification maps have been produced. The mapping information will be used in the development of Water Management Plans.

The Township of Langley derives a large portion of its municipal drinking water supply from groundwater. Groundwater is also used as a water supply by many agricultural, aquacultural and industrial facilities, as well as by private well owners. Of the five most accessible and economical aquifers, four are shallow and unconfined, and therefore susceptible to contamination from surface sources. As well, declining water tables in some aquifers indicate that the current and future rates of groundwater extraction may not be sustainable.

The Township contains fourteen major surface watersheds that provide water for fish habitat, agricultural irrigation, and recreational uses. Urbanization in some of these watersheds has had an impact on water quality, peak flow and availability of fish habitat. As well, changing agricultural practices have increased surface water extraction rates and reduced floodplain areas (e.g. by dyking and filling) in many of the rural watersheds.

The Township is ideally suited for the development of a water resources management strategy, based on its dependence on groundwater as a source of water supply, the inherent vulnerability of its aquifers, the quality of its fisheries resources, and the threats to surface and groundwater quality and quantity from pressures related to agriculture and increased development.

The Township of Langley has adopted a Water Resources Management Strategy (WRMS) to protect and manage local water resources. The goals of the WRMS are:

• To provide a clean and sustainable supply of groundwater and surface water for domestic, agricultural and industrial use;

• To conserve and enhance water quality and quantity for aquatic habitat and recreational use; and

• To minimize flooding and erosion.

Within this context, watercourses are mapped and the data entered into the Township’s geographic information system (GIS). The technical information and data collection are meant to feed into planning processes. This will be a proactive way of planning, avoiding the difficulties of the past in which decisions for developing a certain area, or for making designations in the Official Community Plan (OCP), might get made before appropriate studies were done.

Recommendations for the Community Mapping Network:

1. Plan your project before you start: what information you want to collect, how it will be used, what is the best way to collect it, how you will pay for it, what partners you will work with, etc.

2. Design your database/GIS.

3. Train your crews. The data is only as good as those collecting it.

4. Monitor the results as you go, instead of waiting until the field work or data entry has been completed.

5. Try to build in landowner education and encourage private stewardship.

6. Focus at the local government level: encourage partnerships.

In 1998 the Township of Langley initiated its WRMS with the following vision: to balance present and future water supply with demand for development, while maintaining and maximizing opportunities to enhance the quantity and quality of surface water and groundwater. The WRMS is intended to provide the township with a comprehensive and defensible approach to managing the quantity and quality of the local groundwater and surface water. The Township anticipates that by developing and implementing this strategy, it will move from a position of reacting to individual problems in an ad hoc manner, to a position of proactively managing issues.

The WRMS is an overall strategy for all surface and ground water in which mapping work (which is ongoing to the present time) forms an important component. The Township initiated the mapping of fish habitat and creeks in 1993, before the WRMS was embarked on, as a process of information gathering. The fact that eight years of mapping has already been done propels the Township forward to being able to use the information to make management decisions.

An Action Plan developed under the WRMS has been formally adopted by Langley Township council. This Action Plan will provide the Township with a 20-year schedule of projects to address water resources issues in four categories: groundwater quantity, groundwater quality, surface water quantity, and surface water quality.

Detailed mapping of streams and fish habitat in the Township of Langley was initiated by the Township in 1993, predating the development of SHIM standards. The mapping was carried out by the Langley Environmental Partners Society (LEPS), which was instrumental in the development of SHIM standards.

Some 800 km of watercourses have been mapped; this work is more or less completed. Over 17,000 points of features that were found along the creeks have been recorded, entered into a database, and displayed on GIS.

The stream survey data has been integrated into the Township’s GIS, and watercourse classification maps have been produced. These provide the Township with a useful planning tool. The information will help the Township of Langley to save staff time and costs in managing its watercourses and setting up agreements, and by streamlining environmental approval processes.

By the use of Sensitive Habitat Inventory and Mapping (SHIM) and earlier methodologies the Township now has accurate stream and fish habitat mapping, putting it in an advantageous position in dealing with surface water matters and in developing policy and bylaws. In implementing the WRMS Action Plan and watershed management plans (WMPs) in years to come, the Township will have a significant head start and will move ahead faster in those areas where work has been done.

Anticipated benefits of the watercourse mapping information include:

• More local management of water resources

• More detailed community planning

• Memoranda of agreement to be developed with senior environmental agencies

• Common ground between various players — community, local government, senior agencies, any other community groups — all using the same information

• Having the most up-to-date and accurate information

• Moving ahead on management decisions, agreements, water management plans, and streamside protection regulations

• Reduced costs to the Township of hiring consultants as it may be less necessary

• Reduced costs to landowners who may not have to hire a consultant to do a full environmental assessment if the appropriate agencies already accept creek coding as it is

• Decreased uncertainty for developers, who will know from the start if a stream is fish-bearing

Some streams were discovered in the course of mapping. Some surface water pollution problems were also found, raising concerns for groundwater. The quality of groundwater, a source of drinking water in the Township, is an identified public concern.

Landowner approval to access properties was anticipated to be a greater challenge than it turned out to be. The multi-partner nature of the project was an advantage in this respect, as crews were able to present a variety of objectives for the project, resulting in approval from most landowners.

The various partners who contributed a substantial portion of the project funding were able to meet their objectives in a more cost-effective manner than by doing it alone.

The next steps are to apply the information that has been collected in ways that will be directly useful to staff and to the public.

Mapping information will be used in the development of WMPs. As part of the WMPs, it is a goal to develop separate memoranda of agreement with senior environmental agencies for dealing with stream-side protection regulations, taking a flexible approach to produce long-term agreed-on plans. SHIM mapping provides a level of detail that gives the planning process a huge head start in defining clearly the objectives of those plans.

The Township aims to make use of the stream information to streamline procedures and protocols for landowners requiring the information, as well as for its own staff.

Thanks are due to all the funders and partners. Special thanks go to Brad Mason of Department of Fisheries and Oceans and Rob Knight of Ministry of Water Land and Air Protection for their ongoing support.

The Township of Langley provided all the necessary equipment and system updates plus GIS expertise and technical support.

Langley Environmental Partners Society not only conducted the work, but championed the project. Special thanks to the stream survey coordinator for ongoing dedication, and to the stream survey crews for taking on any challenge!

Thanks to the landowners who allowed crews on to their property.

Community stewardship groups played a helpful supportive role in community education.

Hans Schreier of the University of British Columbia set up the GIS system.

This case study was prepared by Glen L. Porter (G.L. Porter Consulting) with assistance from Marina Stjepovic (Township of Langley) for the ‘Planning Sustainable Communities Workshop’ sponsored by the Community Mapping Network (www.shim.bc.ca) and the Township of Langley. The workshop, held March 15, 2002, showcased examples of mapping as a tool for sustainable planning. These examples were compiled in the workshop’s summary document ‘Planning Sustainable Communities’ by Glen L. Porter with support from Brad Mason (Fisheries and Oceans Canada); Rob Knight (Ministry of Water, Land and Air Protection); Gretchen Harlow (Environment Canada); and, Kathleen Moore (Environment Canada). These case studies were later added to the BC Stewardship Centre Case Study Library by Sara Muir Owen with support from Rod Silver (Habitat Conservation Trust Fund).

References:
Golder Associates Ltd. 2001. Draft final report.

Township of Langley
Marina Stjepovic
Environment Coordina
4914 – 221st Street
Langley, BC Canada
V3A 3Z8
Email: mstjepovic@tol.bc.ca