An existing floodgate set into a grassed farm drain bank.

Siphonic Systems / Farm drainage

Give trapped water a way out.

Carry collected water over stopbanks and awkward ground to a lower outlet. Explore how a Siphonic Transfer Unit could lower the resting water table and bring wet ground back into use.

Explore the possibilities See below the surface

Existing floodgate · Morelands

Illustrative wet pasture with standing water and open drains.

Lower the water table.
Make more of your land.

Illustrative wet-ground context

Wet ground can limit where you graze, when you get machinery on and how much of a block you can use.

More room for roots.: A lower resting water table can improve soil aeration below the surface.
More of the block in play.: Target the wet areas that restrict grazing and access, with the aim of recovering usable land.
More capacity before rain.: Lowering resting groundwater can create space in the soil profile to receive water.

Your soil, intake and outlet level determine the opportunity.

See the reported change at Morelands

Optional groundwater collection

Reach below the surface.

Three distributed spear intakes in a continuous soil section, connected by flexible fittings to a shared collection pipe. — Illustrative intake arrangement

Many collection points. One route onward.

The collection line carries water from the groundwater intakes to the Siphonic Transfer Unit.

Close-up of one spear straw, showing its connection to the common pipe, top collar and lower intake position within the soil section. — Connection and intake detail

Groundwater enters below the surface.

The lower intake collects groundwater. A flexible connection joins each straw to the collection line.

Continuous soil section with saturated ground shown as darker damp earth below a conceptual water table that dips toward each intake. — Conceptual groundwater response

Lower the water table around the intakes.

As groundwater is collected, the water table falls around each intake.

Soil above the water tableSaturated soil

Depth and spacing depend on your soil and the available outlet level. Conceptual illustration · not to scale.

Working with your farm

Build on the drainage you already have.

Open drains, subsoil drains and floodgates can remain part of the solution. A Siphonic Transfer Unit adds extraction where collected water is still being held inland.

An open drain runs between cropped land and pasture at Narbey Farm. — Narbey Farm / Existing drainage
At Narbey, the system draws from the stopbank drain, a valley drain and the foot of the hills.
Source: Narbey installation film

Your drains collect.

Open and connected subsoil drains bring water together. They remain part of the drainage network.

The unit adds extraction.

New intake points can give collected water another route to a lower outlet, alongside existing floodgates.

The design joins them up.

A site survey identifies where to collect water, how to connect the route and whether drain regrading or other works are needed.

Farming with the tide

Put low tide to work.

Lower inland water when the outlet is low, with automatic protection against backflow through the unit.

At low tide the inland drain at left is higher than the outlet water surface at right. A continuous pipe connects submerged ends through the Siphonic Transfer Unit at the stopbank crest. — **Inland drain**Higher water levelOver the stopbankUnit at the crestOutlet water surfaceLower water level

The same section with tidal water now above the inland drain. Reverse flow through the unit is stopped by its internal non-return flap; that internal mechanism is not shown. — **Inland drain**Same reference levelBackflow stoppedInside the unitOutlet water surfaceNow above the drain

Illustrative section · not to scale · water made transparent to show the route

Low tide

Draw water off the farm.

When the outlet water sits below the inland water, the siphon can lower connected drains and groundwater. That creates room for more water in the drains and soil before the next tide or rainfall.

Reverse pressure

Stop tidal water coming back.

As the tide rises, the driving difference reduces. If tidal water tries to flow back through the siphon, the unit’s internal non-return flap closes automatically.

At Narbey, the system uses the Kaipara River’s low tide to draw from inland drains.See the installation

Backflow protection acts within the siphon. It does not stop water overtopping a stopbank.

Automatic priming. No grid connection.

The Siphon Primer takes care of establishing and maintaining prime. It removes air and can automatically re-establish prime after air enters the line, using water recirculated within the system.

Annual primer service. Clear intakes.

The primer is serviced annually. Intake care is separate: keep the collection point clear so water can reach the system.

Siphonic Transfer Unit with primer above the manifold and the gear-driven isolation valve on the right. — Siphon Primer
Removes air to establish and maintain prime.
Gear-driven isolation valve
Provides isolation at the manifold for servicing. Operated using the handwheel.

What goes into the cost.

Compare the route, intake works, installation and annual primer servicing alongside drain improvements or a pumped option.

See siphonic transfer on real farms.

Morelands pasture, cattle and open drainage routes seen from above.

Morelands Farm

A change below the surface.

225 mm: lower resting groundwater table
400 mm: lower open-drain level

Owner/operator-reported observations. One site, one measurement year. Outcomes depend on the site.

Watch the Morelands field film

Still frame · Morelands field film

Installed Siphonic Transfer Unit and pipe beside the Narbey field drain.

Narbey Farm

A way beyond the stopbank.

Follow the installation from the long internal drain, across the stopbank and into its low-tide drainage window.

Watch the Narbey installation film

Still frame · Narbey installation film

Let’s find the opportunity on your farm.

Tell us where water is holding you back. We’ll start with your land and existing drains, then establish feasibility from surveyed water levels.

Discuss your farm Or call Tom on 027 590 2090

A useful starting point

Where water is held: The wet area and the drain, sump or other collection point.
What is already there: Existing drains, floodgates, pumps and any known route constraints.
What you want to improve: Better access, recovery after rain, or a different way to manage collected water.

Already have water levels and a route?

Open the site calculator

Explore an initial hydraulic estimate before a detailed site assessment.