For watering, water quality matters less than for drinking, but quantity matters: the spike well and the pump must deliver as much as the hose or irrigation system demands. Spike well installation costs from €350, the pump is extra.
How much water you need for watering
A simple calculation: 1 millimetre of water on 1 m² is 1 litre. In dry weather a lawn is often given about 10 mm at a time, so 10 litres per square metre.
| Area watered | Per watering (10 mm) | Example |
|---|---|---|
| 100 m² | 1 m³ | beds and a greenhouse |
| 500 m² | 5 m³ | lawn around a house |
| 1,000 m² | 10 m³ | large lawn |
Speed matters too. Sprinklers and automatic irrigation need a certain flow in litres per minute and a certain pressure. If the spike well gives less, the watering is split into zones that switch on one after another. In your request, state the area to be watered and, if you have them, the requirements of your irrigation system.
10 m³ per day: the limit you need to know
Watering is almost the only household case where you can approach the limit set by the state. A spike well, like any other borehole, is exempt from a licence only if it is no deeper than 20 m and no more than 10 m³ of water is intended to be extracted per day. Natural resources tax on groundwater is payable only if more than 10 m³ is extracted per day.
An ordinary garden is far from this limit. If you water a large area every day or fill a pool, calculate the consumption before choosing a system. More detail: natural resources tax.
The law “On Subterranean Depths”, Section 11, paragraph one, point 2: dug wells and boreholes up to 20 m deep need no licence if no more than 10 m³ is intended to be extracted per day. LBN 222-15, point 64: driven wells are water abstraction boreholes. The Natural Resources Tax Law, Section 19: tax on water abstraction above 10 m³ per day. Sources: likumi.lv, checked 03.11.2026.
Which pump and what to add to the irrigation system
- For a hose and sprinkler, a surface pump with a switch is enough. Automatic irrigation needs a pump with pressure control that switches on when a valve opens.
- Fit a mechanical filter before drip irrigation lines. Otherwise fine sand and iron deposits clog the drippers.
- The pump must not run dry for long. If the spike well's flow is small, the controls need dry-run protection.
- For winter, the pump and above-ground pipes are drained just as at a summer house: spike well for a summer house.
We explain choosing and installing pumps on the page water pumps and pressure tanks.
Iron in the water: rust stains on paving and walls
Groundwater often contains dissolved iron. For watering it is usually no obstacle, but when sprayed on paving, tiles, a facade or a fence, the water dries and leaves brownish rust stains. So point the sprinklers away from buildings and paths, or test the water first. A water test shows the iron content, and then you can decide whether you need water treatment or whether careful placement of the sprinklers is enough.
A garden spike well when the house has mains water
Many houses in Riga and the Riga region are connected to mains water (public water supply), and the spike well is installed for the garden only. In that case the spike well system must be completely separate, with no shared connection to the house water main, so that groundwater cannot get into the public network. Clearly mark the garden tap as watering water so that nobody drinks from it.
How the work is done
We choose a spot close to the area to be watered or to the irrigation system's manifold, so the pipe is short. We install the spike well, carry out test pumping and check how much water it gives. Then we choose a pump that matches this flow, not the other way round. Spike well design and the course of the work: spike well.
How much a spike well for watering costs
Spike well installation costs from €350, usually €350–650. The pump, filter, pipe to the irrigation system and the system itself are charged separately. The price depends on the depth to the water-bearing layer, the soil and access. All prices: prices.