2026 restriction update: Metro Vancouver introduced Stage 3 restrictions on June 8, 2026. Stage 3 remains in effect until July 16, when the region will move back to Stage 2. Stage 2 is expected to continue until October 15 unless Metro Vancouver announces another change.
Metro Vancouver’s summer water restrictions limit how you can use water from the regional drinking water system. They do not prevent you from installing rainwater collection, non-potable storage, pumps, filters, or drip irrigation.
More importantly, the restrictions do not apply to rainwater, grey water, recycled water, or water from another source outside the Greater Vancouver Water District and municipal water supply system.
That creates a practical opportunity for homeowners, strata properties, businesses, schools, and municipalities. You can install a system now that reduces your dependence on treated drinking water through the June-to-October irrigation season.
What Stage 3 allows
Under Stage 3 restrictions, you cannot use municipal drinking water to irrigate an existing lawn.
You can still:
- Water trees, shrubs, flowers, and other inedible plants using drip irrigation.
- Hand-water with a container or a hose equipped with a spring-loaded shut-off nozzle.
- Water vegetable gardens at any time.
- Use properly managed rainwater or another non-potable water source because it falls outside the regional drinking water restrictions.
Sprinklers, soaker hoses, ornamental fountain filling, residential pool filling, driveway washing, and general vehicle washing are restricted when they use municipal drinking water.
Your municipality enforces the restrictions. Confirm local bylaws before installing or operating a system, especially if you plan to connect it to building plumbing or an existing irrigation network.
Install a roof-fed rainwater tank
A basic rainwater collection system diverts water from your roof into a storage tank.
A small installation can include:
- A downspout diverter.
- A debris screen.
- A covered rain barrel or storage tank.
- A controlled overflow connection.
- A hose outlet or watering-can tap.
This is often the fastest option for planters, raised beds, small vegetable gardens, and hand-watered landscaping.
The City of Vancouver recommends selecting a rain barrel with an overflow connection, child-resistant opening, screen, hose connection, and faucet. It also states that collected rainwater should not be used for human consumption.
A 200-to-500-litre barrel can help with small garden areas. However, it may empty quickly during a prolonged dry period. Connecting several barrels or installing a larger tank provides a more useful irrigation reserve.
Connect stored rainwater to drip irrigation
Stage 3 permits drip irrigation for trees, shrubs, and flowers, including when the water comes from the municipal system. Using collected rainwater provides an additional benefit because you offset treated drinking water use.
A pumped drip system typically includes:
- Rainwater storage.
- An appropriately sized pump.
- An intake screen.
- A filter that protects the emitters.
- A pressure regulator.
- Distribution pipe.
- Dripline or individual emitters.
- Isolation valves.
- A controller or timer.
Drip irrigation places water close to the plant root zone at a low flow rate. The Province of British Columbia’s irrigation guidance identifies flow requirements, filtration, emitter selection, pressure, water treatment, and irrigation scheduling as core design considerations.
Do not connect an untreated rainwater line directly to your drinking water system. Keep the systems separated and clearly identified.
Install a larger aboveground or underground cistern
A larger tank gives your property a buffer between rainfall events.
This matters in Metro Vancouver because the region receives significant annual rainfall, but July and August are relatively dry. Vancouver Harbour’s 1991-2020 climate normals show average precipitation of 43.5 millimetres in July, 48.6 millimetres in August, 71.4 millimetres in September, and 156.8 millimetres in October.
A larger system can support:
- Multi-zone drip irrigation.
- Vegetable gardens.
- Trees and shrubs.
- Commercial landscaping.
- Strata common areas.
- School or institutional gardens.
- Future approved indoor non-potable uses.
Aboveground tanks are usually easier to install and inspect. Underground tanks preserve usable yard or parking space but require excavation, structural planning, access risers, overflow management, and suitable equipment for vehicle or soil loading conditions.
How to calculate your rainwater supply
One millimetre of rain falling on one square metre of roof produces approximately one litre of water before collection losses.
Use this formula:
Rainwater collected in litres = roof area in square metres × rainfall in millimetres × collection factor
For preliminary planning, a collection factor between 0.80 and 0.90 can account for splash, first-flush diversion, evaporation, gutter losses, and tank overflow.
Example
A property has:
- 150 m² of connected roof area.
- 20 mm of rainfall.
- A collection factor of 0.85.
The potential collection is:
150 × 20 × 0.85 = 2,550 litres
Using Vancouver Harbour’s normal July rainfall of 43.5 mm, the same roof could theoretically collect about 5,550 litres during the month. Actual usable collection will depend on rainfall timing, tank capacity, system losses, and how quickly you use the stored water.
A 1,000-litre tank may overflow during one heavy rainfall event and then run empty during the following dry period. Tank sizing must account for both total monthly rainfall and the length of time between storms.
How to calculate irrigation demand
Start with the area you plan to irrigate.
For preliminary residential planning, you can use 15 litres per square metre per week for established, efficiently drip-irrigated planting beds. Use a higher allowance for vegetables, new plants, sandy soil, exposed areas, and hot weather.
Use this formula:
Weekly irrigation demand = irrigated area × litres per square metre per week
Example
A 100 m² garden using 15 litres per square metre requires:
100 × 15 = 1,500 litres per week
A full 3,000-litre tank would provide approximately two weeks of irrigation before allowing for inaccessible tank volume, pump protection levels, filter flushing, leaks, and other losses.
Preliminary tank sizing for BC properties
The following examples use an initial demand allowance of 15 litres per square metre per week. They assume the tank starts full and receives no additional rainfall.
| Tank capacity | Example irrigated area | Approximate reserve |
| 1,000 L | 50 m² | 9 days |
| 2,500 L | 100 m² | 12 days |
| 5,000 L | 150 m² | 16 days |
| 10,000 L | 250 m² | 19 days |
These figures provide a starting point. Your actual requirement may change based on:
- Plant type and maturity.
- Soil texture and drainage.
- Sun and wind exposure.
- Mulch depth.
- Irrigation efficiency.
- Available roof area.
- Local rainfall.
- The reserve period you want.
- Whether the tank serves irrigation only or several non-potable uses.
For a stronger summer buffer, size the tank for two to four weeks of critical irrigation demand rather than trying to supply every landscaped area.
Components to plan before ordering a tank
A reliable system requires more than storage capacity.
Confirm the following:
- Connected roof area and roofing material.
- Available installation footprint.
- Tank height and access restrictions.
- A stable, level foundation.
- Downspout locations.
- Leaf and debris screening.
- First-flush or water-quality controls.
- Emergency and normal overflow routes.
- Pump flow and pressure requirements.
- Irrigation zone flow rates.
- Filtration suitable for the selected emitters.
- Protection from cross-connections.
- Inspection and cleaning access.
- Freeze protection and winterization.
- Whether excavation or municipal permits are required.
Overflow needs particular attention. A tank can fill rapidly during BC’s fall and winter storms. Overflow should discharge to an approved location without affecting your foundation, neighbouring properties, slopes, or public areas.
Install for Stage 3, keep the benefits year-round
A rainwater harvesting system can help immediately during Stage 3 restrictions. It can continue reducing treated drinking water use after restrictions return to Stage 2 or Stage 1.
The best system is not automatically the largest tank. It is the system that matches your roof collection potential, critical irrigation demand, available space, pump requirements, and intended non-potable uses.
Start by measuring three things:
- Your connected roof area.
- Your priority irrigation area.
- The number of dry days you want the system to cover.
Those numbers provide the foundation for selecting the tank, pump, filtration, and irrigation equipment your property actually needs.
