Septic tanks and BIO plants in Mangaļsala - summer houses and detached homes by the sea

Mangaļsala: sand, sea wind and seasonal homes

In Mangaļsala, the defining conditions are the sea wind, dunes, sand and coastal forests, along with seasonal visitors. For sewerage, this means an uneven load: on a summer weekend with guests, the tank fills several times faster than in autumn, while in winter it can stand almost unused.

That's why, before giving any advice, we ask how many months a year the house is lived in, by how many people, and whether there is a shower, washing machine or sauna. This decides whether a holding tank is enough or you need a septic tank with infiltration.

For a seasonal home: a septic tank or holding tank, less often a BIO plant

A biological plant needs a constant inflow of wastewater. If the house stands empty for weeks, the activated sludge weakens, and after you return the plant treats the wastewater poorly for a while. That's why summer houses usually get a septic tank or holding tank, and BIO plants are left for homes that are lived in permanently.

• Only a sink and a toilet, little water: a sealed holding tank is enough.
• A shower, washing machine or sauna: you need a septic tank with infiltration.
• Living there all year round on a small plot: a BIO plant is suitable.

Sizes and solutions for garden houses: septic tank for a summer house. The holding tank option: holding tank installation.

Sandy soil and infiltration

Sand lets water through well, so a drain field or filtration well in sandy soil usually works much better than in clay. Near water, however, the groundwater level at the specific spot must be checked: between the bottom of the infiltration and the groundwater there needs to be a layer of dry sand that treats the settled water.

Near dunes and coastal forests, also find out before digging what the spatial plan allows on the plot. How a drain field works and how it is built: drain field.

Where to place a new tank

If the summer house plot is narrow, it is tempting to hide the tank at the far end of the garden. But a vacuum tanker will have to reach it every year, so it is better to choose a spot closer to the gate or driveway. A shorter pipe from the house is also cheaper and less likely to freeze.

Digging a pit in sand is easy, but its sides cave in, and after installation the tank must be backfilled with compacted sand evenly on all sides so that it isn't crushed.

In autumn: pumping out before closing up the house

• Plan the last pumping before you leave for the winter, because the contents of a full tank can freeze in the frost, and frozen contents cannot be pumped out.
• If the tank is plastic and the groundwater is close, we leave some water in the tank after pumping so that it isn't lifted out in spring.
• Drain the water pipes in an unheated house, and check that no water is standing in the inlet pipe.
• Mark the position of the lid with a stake, so that you can find it in spring even under windblown sand or snow.

If the tank freezes in winter anyway: frozen septic tank.

Access via Vecāķi and Vecdaugava

Mangaļsala is reached by a narrower network of access roads from the direction of Vecāķi and Vecdaugava. On a narrow street or a sandy driveway, a smaller truck (up to 4 m³) is easier to work with. In your request, state the width of the road and the gate, and whether the truck can drive up to the lid or the hose has to be run.

On summer weekends, when the coast is busy with holidaymakers, it is harder to drive in and stop, so pumping is best planned on a weekday or outside the season.

Riga's rules also apply to summer houses

Mangaļsala is within Riga, so a summer house's septic tank or holding tank has the same requirements as a permanent home. The system must be registered with the Riga Housing and Environment Department, septic tank sludge is removed at least once a year, and a declaration on the volume removed is submitted by 1 May.

For a holding tank, Riga calculates the minimum frequency from water consumption and volume. If there is no meter, 9.125 m³ a year per declared resident is assumed, as if the house were lived in all year. For a seasonal home with a water meter, a calculation based on actual consumption is closer to reality. Keep the certificate for every septic tank pumping in Mangaļsala for at least two years.

Nearby neighbourhoods

On the coast and along the lower Daugava, we also work in Vecdaugava, Vecāķi, Vecmīlgrāvis and, on the other bank of the river, Daugavgrīva. All areas: where we work.