ANNOUNCEMENT: BC Landscape Water Calculator is available to all residents of British Columbia

Editor’s Context:

“The rhythms of water are in flux – winters are warmer and wetter; summers are longer and drier. This is British Columbia’s new reality. Adapting means that we must view water differently. Adapting requires that our use of water be in balance with a changing water cycle.  A core concept for an adaption strategy is this: Water sustainability in the built environment would be achieved through implementation of green infrastructure policies and practices.” states Kim Stephens, Waterbucket eNews Editor and Executive Director, Partnership for Water Sustainability in British Columbia.

“The Partnership for Water Sustainability develops tools and resources for use by communities to facilitate a ‘design with nature’ approach to water-centric planning in British Columbia. The newest tool in the Partnership toolbox is the BC Landscape Water Calculator. Simply put, it is both a decision support and educational tool for local government water conservation programs.

“Now live at, the calculator is in the public domain. This means it can be accessed and used by all BC local governments for water resiliency planning and management of outdoor water use. Integration of the BC Landscape Water Calculator, as a foundation piece for water conservation programs, would help communities bring to fruition the vision for water sustainability.”


“The BC Landscape Water Calculator is linked to a 500 metre gridded climate data set covering the entire province. The tool allows any property owner in BC to zoom in to their property and quantify their landscape water needs based on climate, soil, plant type and irrigation system,” states Ted van der Gulik, Partnership for Water Sustainability in British Columbia

City of Kelowna is a Project Partner

In the article below, Ted van der Gulik shares the ‘story behind the story’ of the BC Landscape Water Calculator. His storyline is structured in three parts: partnerships and collaboration benefit everyone; the calculator is science-based; vision for mainstreaming province-wide. The City of Kelowna is featured because it is the first local government to become a project partner.

“The City’s participation as a project partner is key because the BC Landscape Water Calculator supports Kelowna’s water regulation bylaw and Qualified Water Efficient Landscaper program (QWEL). In addition, the City facilitated a grant from the RBC Blue Water Project to jointly fund tool development,” reports Ted van der Gulik.

The BC Landscape Water Calculator is an outcome of a multi-year investment by the provincial government and other partners to develop science-based tools. It is the latest spin-off tool from the BC Agriculture Water Demand Model. Another spin-off tool is the BC Agriculture Water Calculator which supports the provincial government’s application process for all new water licences. The catalyst for developing these tools is Living Water Smart, British Columbia’s Water Plan.

Quotable Quote:

“The City Utility is excited to promote this online water tool to our residents. It makes the process of understanding, calculating, and submitting water use reports to the City so much easier and user-friendly,” stated Ed Hoppe, Water Quality and Customer Care Supervisor, City of Kelowna. “It also highlights the importance of making conscious water decisions while still making your landscape look fantastic. Win-win for everyone!

“The Qualified Water Efficient Landscaper (QWEL) certification program is a great way for homeowners to ensure that landscape and irrigation contractors have water conservation in mind, consider native landscape material, and provide top notch workmanship in their services.

“The QWEL training program provides graduates with knowledge in water efficient and sustainable landscapes and asks that they uphold the standards presented during the training.  QWEL certified contractors, designers and other successful participants agree to adhere to the requirements of the Landscape Water Conservation Report per Bylaw 10480, and to follow residential irrigation standards, in order to remain on the Kelowna QWEL Contractor list.”

Ray Warren – Vice President, RBC Commercial Financial Services. Ed Hoppe – City of Kelowna Water Quality and Customer Care Supervisor. Courtney Hesse – RBC Regional Vice President

Partnerships and Collaboration Benefit Everyone

“Over the past decade, the City of Kelowna has implemented innovative approaches to management of water use and landscape irrigation, such as the QWEL program. Therefore, it was a natural fit for the Partnership and City to collaborate in the development of the BC Landscape Water Calculator,” states Ted van der Gulik, President, Partnership for Water Sustainability in BC.

“A platform re-build for the BC Agriculture Water Calculator was the opportunity to spin-off the BC Landscape Water Calculator as a stand-alone tool for use by local governments and their residents. At the same time, the City of Kelowna was implementing a landscape bylaw that established an allowable water budget at the individual property scale.”

About Ted van der Gulik:

When he retired from government in 2014, Ted van der Gulik was the Senior Engineer in the BC Ministry of Agriculture. He had a leadership role in provincial initiatives related to water use and management.

Three decades ago he had a vision for a science-based approach to management of water demand in British Columbia. In June 2008, the stars aligned when the provincial government released Living Water Smart, British Columbia’s Water Plan. This was a defining moment in BC’s water history.

Living Water Smart provided the policy framework for a new era of water management in BC. Living Water Smart was a catalyst for action because it established 45 actions and targets for doing business differently, preparing communities for change, and choosing to be water smart.

Ted van der Gulik had a mandate  that allowed him to put his ideas into practice through province-wide implementation of the Agriculture Water Demand Model program. Through a partnership agreement between the Province and the Partnership for Water Sustainability, he has a continuing management responsibility for ongoing program delivery.

Currently, he is responsible for overseeing delivery of  the spin-off suite of online calculators.


How Outdoor Water Use is Managed

“The City of Kelowna has an oversight system in place to ensure that landscape design and irrigation design work together to achieve water efficiency. The City’s approval process is keyed to three requirements:
  • Limit use of turf-grass to a maximum of 60% of the site.
  • Design the system so that water use would not exceed the allowable annual water budget.
  • Submit a Landscape Water Conservation Report for the City’s approval.

“The Irrigation Industry Association of BC also became a project partner. The significance of IIABC involvement is that IIABC provides training for landscape irrigation designers and contractors. These trained individuals help support implementation of the City’s QWEL program.

“We also involved the Okanagan Xeriscape Association as a technical resource. OXA assisted with development of a database of nursery plants that are water efficient, drought resistant, and suitable for Okanagan conditions. Currently, this database is only connected to the landscape calculator for use in Kelowna. Basic plant information is used for the rest of the province.”

BC Landscape Water Calculator is Science-Based

“The tool educates users because they are able to compare water use for separate landscape profiles. By following the Users Guide, and through experimentation with the dropdowns, they learn that ‘water need’ varies depending on plant type, irrigation system, local climate and soil type.”

Linked to Provincial Database

“Most importantly, the tool allows the users to divide their properties into ‘hydrozones’, otherwise known as planting areas. Then they can test various combinations of plant types and irrigation systems. The objective is to be at or below the allowable water budget.

“The power of the tool is that it is linked to the provincial database for the Agricultural Water Demand Model, in particular the 500 metre gridded climate cells. This is what establishes the allowable water budget. It is a real number based on climate data averaged from 2000 through 2010.

“Customizing of the tool for use within Kelowna included plant selection dropdowns developed with assistance from the Okanagan Xeriscape Association. This led us to go the next step and take into account whether there is sun exposure or shade. The database also provides the user with guidance as to whether plant selections are suitable for sun exposure or shade. Think about why that is important.”

Enhanced Resiliency

“In summary, a key takeaway message is that the BC Landscape Water Calculator has benefited from a major provincial investment in a science-based approach to quantifying how much water is needed for irrigation.

“Now any property owner in BC can zoom in to their property and quantify their outdoor water need based on climate, soil, plant type and irrigation system. We believe this is quite likely the first application of this kind in the world. Over time, province-wide use of the tool would result in enhanced resiliency of community water supplies.”

To Learn More:

The Partnership for Water Sustainability invites you to test drive the BC Landscape Water Calculator at Click on the image to watch an online demo of the tool.

Partnership Vision for Mainstreaming Province-Wide

“In the coming months, the Partnership for Water Sustainability will proceed with an outreach program. An early priority is to raise awareness of the BC Landscape Water Calculator as a ‘made in BC’ tool for water resiliency planning and regulation of outdoor water use. This announcement is a first step.

“Our vision is that province-wide mainstreaming would begin in 2021. In the meantime, we invite expressions of interest from local governments wishing to be part of the program. Contact us at

“While anyone in British Columbia can now use the calculator, there are benefits to a local government in becoming a partner in the program. As the City of Kelowna experience foreshadows, incorporating local knowledge and requirements would stimulate local uptake of the tool.”

Whole-System, Water Balance Management: 

“At some point in the foreseeable future, the Partnership envisions there will be an opportunity to interlink the BC Landscape Water Calculator and the Water Balance Model Express for Homeowners.

“The latter is a wet-weather tool for rainwater capture and protection of stream health. Like Lego, homeowners can add building blocks to test how to infiltrate rainwater runoff on their property, and thus reduce discharge to municipal drainage systems.

“The commonality is soil and how soil functions as an absorbent sponge to hold and slowly release water, thereby maintaining the water balance during wet and dry cycles. Once the tools are interlinked, it would be within our grasp to achieve whole-system, water balance management at the property scale.”

Click on the image below to test drive the BC Landscape Water Calculator: