Water Rills and Spillways

The steel or stainless channel that holds and guides the water, fabricated to the landscape drawing. The pump, plumbing and controls stay with the water-feature designer.

Request a Quote
See configurations

TrussMetal is a metal fabrication shop in North Vancouver. This page is for landscape architects, garden designers and landscape contractors who have drawn a rill, runnel or spillway and need the metal part made. A rill is a narrow open channel that carries water across a garden or courtyard; a spillway or weir lets the water drop from one level to the next.

What we make is the water-holding channel, its lips and weirs, and the frame it sits on, not the complete water feature. The pump, pipework, reservoir or sump, filtration, controls, wiring and the surrounding paving are designed and installed by others, and the quote names who does each.

Configurations

In-ground rill channels

A narrow channel set into paving, gravel or lawn, with its top edge at or just above the finished surface. Made in lengths that can be handled, coated and joined on site.

Raised and wall-top channels

A channel carried on a seat wall, a planter edge or a steel frame, so the water runs at a height people see and can reach.

Spillway lips and weirs

A fabricated lip, weir plate or scupper that lets water sheet or pour from a channel, basin or wall into the level below.

Stepped channels

A run of channels or shallow trays that steps down a slope, each spilling into the next, ending in a pool or sump built by others.

Concept drawingIn-ground rill channel (section)Section through a welded channel set in paving: the water level comes from the water-feature design, and the paving and the base under the channel are by others.Paving by othersWater level set bythe water designWelded channelBase or bedding by others
Concept drawingSpillway lip (section)Section through the end of a channel: water spills over a fabricated lip as a sheet into a pool or basin below, which is by others. The lip profile follows the water-feature design.Lip profile fromthe water designWater sheetPool or basin by othersSection
Concept drawingRill with sump and return (plan)Plan of a channel from its inlet to a spill lip at the far end, falling into a sump; the sump, pump and the return pipe back to the inlet are by others.ChannelInletSump, pump andpipework by othersReturn pipe by othersPlan
Conceptual drawing for planning only. Not a photograph or record of completed TrussMetal work; final detailing is drawn for each project.

Not part of this page: ponds and pond liners, pool and spa components, fountains with spray nozzles, stormwater drainage channels, and retaining walls. Planters, including ones a rill runs beside or spills into, are on custom planters; where a channel meets a planter, the planter’s drainage and waterproofing are detailed with it.

Who Sets What

Levels and falls
Set by the landscape architect or water-feature designer and established on site by the landscape contractor. Some rills are built level and the water runs over a weir; others fall along their length. We fabricate to the levels and falls drawn and point out anything that can’t be built as shown.
Outlet and spillway geometry
The lip profile, weir height, outlet position and outlet size come from the water-feature design, because they depend on the flow the pump delivers. We make them to that design.
Connections
Inlet, outlet and overflow openings are made to suit the fittings the water-feature contractor or plumber specifies. The pipework, pump, filtration and controls are theirs, and power to the pump is the electrician’s.
Support
A full channel needs continuous, even support so it doesn’t move or flex. The base or bedding under an in-ground channel is by the landscape contractor; supports for a raised channel or one carried on a frame are detailed in the quote.
Maintenance access
Grates, removable covers, clean-outs and access to the pump or sump are agreed at design stage, so leaves and debris can be cleared and the feature drained.
Winter
How the feature is drained or protected from freezing is part of the water-feature design; the channel is detailed to drain where that design needs it.

Water and Materials

A rill can be wet all the time, or for months at a time, so the material is chosen for the water it holds and for continuous immersion, not just for how it looks.

Stainless steel
Usually 316 for an outdoor water feature. The grade is checked against the actual water: chlorinated, salt or softened water, de-icing salt that can reach the channel, and any treatment the water-feature contractor plans to use.
Coated steel
Only with a coating system its maker states is suitable for continuous immersion in that water, applied by a specialist applicator and named in the quote. Damage to the coating needs repairing before it spreads.
Weathering steel
Not used where water flows or stands continuously, because it protects itself only when it can dry out between wettings. It can form dry surrounds and edges kept clear of the water, with run-off staining considered.
Mixed metals
Fixings, grates and fittings that touch the channel are chosen so dissimilar metals don’t corrode each other in water.
What we need
The water source and how it will be treated. If that isn’t settled yet, the quote states the assumption it was priced on.

Watertightness

Seams are welded, and joints made on site are welded or sealed as detailed for that project. How the channel is checked for leaks, including the method, how long it is held full, what is inspected and what counts as a pass, is agreed in the quote for each project; we don’t publish a standard test or rating. Once the channel is installed and connected, the water-feature contractor fills and commissions the complete feature.

Who Does What

Responsibilities that affect the quote

TrussMetal: the channel, lips, weirs, end caps and transitions; supports and frames detailed in the quote; openings for the specified fittings; the leak check agreed in the quote; and the finish through a specialist applicator where the steel is coated. Setting the channel on a prepared base can be quoted separately.

Landscape architect or water-feature designer: levels and falls, flow, lip and outlet geometry, the water system, water treatment and the winter strategy.

Landscape contractor: setting out, the base or bedding, paving and planting around the channel.

Water-feature contractor, plumber and electrician: pump, pipework, filtration, controls, power, filling and commissioning.

Related Work

See metalwork for landscape architects, landscape edging and custom planters. For material behaviour, see stainless steel and weathering steel.

Questions

Do you supply the pump and plumbing?

No. The pump, pipework, sump, filtration, controls and wiring are designed and installed by the water-feature contractor, plumber and electrician. We make the channel and its openings to suit their fittings.

Can a rill be made in Corten?

Not where water flows or stands continuously. Weathering steel needs to dry out between wettings to protect itself. Stainless or a coating made for continuous immersion is used for the wet channel.

How do you check that it doesn’t leak?

The method and what counts as a pass are agreed in the quote for each project. After installation, the water-feature contractor fills and commissions the complete feature.

Can a long rill be made in one piece?

Length is limited by handling, transport, coating or galvanizing tank sizes and access to the site. Longer runs are made in sections, with the joints detailed for that project.

Do you work from our drawings?

Yes. Send plans and sections with the levels and the lip and outlet details. If those aren’t fixed yet, send what you have and say what is still open.

Request a Quote

Send the drawings and what you know about the water.

What to include in your message

  • Plan and sections: lengths, internal width and depth, and the water level
  • Levels and falls, and where the water enters, spills and leaves
  • Lip, weir and outlet details, or the flow the designer has set
  • How the channel is supported, and what it sits in or on
  • Water source and treatment, and whether it runs through winter
  • Material and finish preference
  • Who is doing the pump, plumbing, base and installation, and your timing

The form starts blank: in “What do you need?”, select Other Custom Metalwork.

Request a Quote

Sending photos of your pet? After submitting, email 3–6 clear photos — front, side, three-quarter, full body and a close-up of the face — to sales@trussmetal.com with your name in the subject line. Photo tips

Have photos or drawings? Email them to sales@trussmetal.com after submitting this form. A photo of the site is the single most useful thing you can send.

Prefer to talk it through? Call (778) 805-5333, Monday to Friday, 8:30 to 5:00.