WATERSHED HEALTH AND YOU: At the Parksville 2019 Symposium, Gilles Wendling will elaborate on “Groundwater & Surface Water Interaction in the Englishman River Watershed: One Water – Always Moving” (Module B on Day One – panel vignette)

Note to Reader:

At the Parksville 2019 Symposium, Gilles Wendling is a member of a 5-person panel that will prime delegates for a town-hall learning and sharing session that features the Englishman River watershed. The Englishman River ‘big picture’ story (endangered river, regional water source, Shelly Creek restoration) provides the backdrop for developing a shared understanding of what a Whole-System approach looks like, and what it would mean to reconnect hydrology and ecology.

Englishman River Watershed

Groundwater & Surface Water Interaction in the Englishman River Watershed: One Water – Always Moving

‘Flux’ is a core concept because an aquifer is not an underground lake. Water is always moving. Community involvement in a monitoring program was a foundation piece, and one of several innovations, for characterizing surface and groundwater interaction in the Englishman system – e.g. the connections between land, aquifers and river are illustrated using “butterfly” images.

Characterizing Aquifers

Because he looked at groundwater differently in the Englishman River, Dr. Gilles Wendling has advanced the science and he has developed a practical application of water balance thinking. His contributions to science-based understanding extend beyond the technical and into the communication and education realm. His work provides a bridge between rainfall and stream health.

“Characterizing aquifers is a complex and costly exercise because you need wells in order to reach aquifers and to monitor the depth and fluctuation of the level of the water table,” states Dr. Wendling. “The approach that we took with MVIHES in the Englishman River Watershed was to involve the community.”

Dr. Wendling emphasizes that time is a critically important dimension in maintaining the water balance. Also, that water is always moving. These are fundamental concepts, yet are not always well understood.

Groundwater Mapping and Education

In 2009, MVIHES commenced a two-phase Groundwater Mapping and Education initiative led by Gilles Wendling. Program objectives were to create a community-based watershed monitoring and protection program, collect information on the presence and behavior of aquifers in the Englishman River watershed, and define the interconnection between the aquifers and the Englishman River.

“Both phases used a similar approach based on community involvement and aquifer monitoring.  The local community was involved to save the large cost of having to install new wells for monitoring by using existing wells that owners volunteered,” explains Gilles Wendling.

“We believe that the long term health of watersheds depends on the stewardship of the people who live in them.  By getting residents involved, the community connects to its watershed, its complexity, and how it works.

“When we establish a connection we are more willing to modify behavior and management of the land. Because residents are involved in the data collection process, they appreciate the direct connection between what happens at the surface and what happens in the subsurface, on their property, their neighbors property and their local environment.”

To Learn More:

Visit the MVIHES website and go to Groundwater Mapping and Education.

Legacy Resource: A series of videos by Gilles Wendling will continue to inform and educate the public over time

Gilles Wendling has narrated a series of video presentations describing the findings of his 2-year study of groundwater and surface water interaction in the Englishman River lower watershed. The slides in the videos were developed for a public presentation given in Parksville in November 2011.

Part 1 focuses on the identifications of aquifers in the lower Englishman River Watershed and the methodology used for the study.

Part 2 focuses on the assessment of the flux of groundwater discharging to the Englishman River. It provides new and creative images illustrating the interaction between the Englishman River and the aquifers along its banks.

Part 3 describes the role played by groundwater flowing in the bedrock aquifers and the fact it is still predominantly unknown. It also provides a water balance for the Englishman River during periods of low flow, and it reveals that aquifers are the main source of water in the Englishman River in the summer and fall.

Part 4 describes the link between the Englishman River, the aquifers in its watershed, and the land where aquifer recharge takes place. It presents a new and innovative way of illustrating with “butterfly” images the connection between the land, the aquifers, and the river.

The “Parksville Primer” Links Rainfall, the Landscape, Groundwater and Streamflow

Released in April 2012 by the Partnership for Water Sustainability in BC and the Living Rivers Trust, the Primer on Integrated Rainwater and Groundwater Management for Lands on Vancouver Island and Beyond provides a science-based understanding of factors that impact on watershed and stream health, either for better or worse.

Gilles Wendling was a key contributor. The Primer incorporated the findings of the precedent-setting groundwater research project undertaken by Dr. Wendling.

Elements of the Water Balance

Building blocks in a science-based understanding are:

  • rainfall (precipitation);
  • the ability of the landscape to absorb rainfall;
  • movement of water through the ground; and
  • the resulting flow in streams.

These elements are part of a system that we call the Water Balance. Land development short-circuits this system when the land surface is hardened and below-ground flow paths to streams are eliminated. By describing the linkages and connecting dots, the ultimate goal of the Primer is to foster responsible decisions about use and development of land.

“The Primer synthesizes the pioneer work of Gilles Wendling, and presents it in his own words,” states Kim Stephens, Executive Director of the Partnership for Water Sustainability, and primary author of the Primer. “Because Gilles looked at groundwater differently in the Englishman River, he has advanced the science and developed a practical application of water balance thinking. His contributions to science-based understanding extend beyond the technical and into the communication and education realm. His work provides a bridge between rainfall and stream health.”

Collaboration with the City of Parksville

Collaboration with the City of Parksville created the opportunity to inform the educational process that was part of the City’s Official Community Plan Review. For this reason, the Primer is often referred to as the “Parksville Primer”.

“Parksville’s OCP Review in 2012 provided a great opportunity to formally recognize the value and inter-dependence of the City’s small stream and groundwater resources, and their importance to people and the region’s highly diverse fish and wildlife populations.  The term ‘livable community’ can take on new relevance in this process, and ensure Parksville remains a community of choice for residents and visitors alike,” stated Craig Wightman when the Primer was released. A Senior Fisheries Biologist with the BC Conservation Foundation, he was a Primer co-author.

To Learn More:

Read about the delegation to inform Council in January 2011: Parksville City Council introduced to ‘water balance’ approach to watershed sustainability

Look at Groundwater Differently

The Primer introduces building blocks that can inform ‘water-centric’ policy development by BC municipalities. Embedding a science-based understanding in an Official Community Plan (OCP), for example, can make a difference on the ground. Thus, the Primer objectives are three-fold:

  • provide insight into the regulatory and educational context for moving from awareness to action in order to protect watershed and stream health in BC;
  • explain how introduction of the Rainfall Spectrum concept almost two decades ago led us to look at rainfall differently in BC;
  • foreshadow how pioneer research in the Englishman River watershed in the City of Parksville on Vancouver Island can similarly lead us to look at groundwater differently.

The City of Parksville OCP was a demonstration application for the Primer. The learning captured in this Primer continues to be shared with other local governments on Vancouver Island through the Inter-Regional Education Initiative.

Estimated Groundwater Flux to Englishman River from Overburden Aquifers

How Much Groundwater is Discharging to the Englishman River?

“In order to visualize the flux between the aquifers and the Englishman River under low summer flow conditions, we created a series of images,” states Dr. Wendling.

“In the accompanying image (see above), you are traveling down the Englishman River, between 10 km and 5 km up from its estuary.  On your left you see the face of the left bank, and on your right the right bank.  The picture of the land, on both sides allows you to position yourself in the watershed.”

“The blue line represents the elevation of the river. The coloured shapes represent the sections where the aquifers intersect both banks.  And the arrows express the flux of groundwater discharging into the river.”

“The estimate of the flux is summarized in the boxes, in litres per second (l/s) and cubic metres per day (m3/day).  The ratio between the flux from the aquifers and the summer river lowest flow rate is expressed as a percentage, to show how much the aquifers participate in providing water to the Englishman River during its period of low flows.”

Flux Defined

Flux is a core technical concept, and one that Gilles Wendling stresses when making presentations.

“The groundwater flux is the quantity of water traveling through and aquifer (in the voids between the grains of salt or the pieces of gravel) per section area (typically per m2 of the section of the aquifer it is traveling through) and per unit of time (e.g., per second, minute, day, year).

“In my experience, it is important to both remind and emphasize that an aquifer is NOT an underground lake. This fact is not necessarily understood by everyone. So we need to be clear that an aquifer simply consists of saturated layers of sand and gravel in the subsurface. The water is always moving.”

Butterfly Views

“One of the objectives of our project was to delineate the land where aquifers connect to the Englishman River and are being recharged. We created ‘butterfly’ views for this purpose,” explains Gilles Wendling.

“(In the butterfly example included above) we have used the views of both the right bank and the left bank of the river showing where the aquifers are in contact with the river  and have added the footprint of these aquifers, using color coding.

“(Below) we have a shallow aquifer in purple on the left bank.  The purple shaded area shows its footprint.  The thick dash line delineates the boundary of the estimated recharge area.  This is the area where precipitation will generate infiltration that will reach the aquifer and will continue its travel as groundwater discharging into the river.

“On the right bank, the boundary of the recharge area does not correspond to the footprint of the aquifer, because there is a groundwater divide.  Water droplets falling left of the divide (dashed line) will end up in the Englishman River.  The ones falling on the right side will end up discharging into the South Englishman River.”

To Learn More:

The title of the latest study completed by Gilles Wendling for MVIHES is: Groundwater Flow Through Bedrock Contributing to the Englishman River. This report is key to the protection of sensitive areas of this watershed.