How to make drainage on a site - three models of a water drainage system

Tell me how to make drainage on the site? After the rain, there are puddles in the yard for a long time, apparently because the earth is clayey. In addition, this year I noticed that the walls in the garage are wet after winter.

When is drainage needed

You should think about making drainage structures if:

• clay soil on the site (water leaves for a long time and stagnates);
• groundwater is at a depth of less than 1 m;
• the planned buildings will have a buried foundation (it can be washed away by groundwater during a seasonal rise);
• a significant area of ​​the site is covered with paving slabs, asphalt or concrete;
• there is a big lawn or several that are equipped with automatic irrigation;
• the walls of a house or other buildings after winter are damp, covered with mold, and there is often water in the basement or cellar.

Low-lying and slope areas also need drainage. It will prevent flooding of the yard and washing out of the fertile layer of the earth. Flat terrain is no exception: without drainage, water will go deep into the depths. Its presence is especially important if there are fences in the form of a fence with a strip foundation around the perimeter of the site.

Drainage can be superficial, closed (deep) or backfill.

How to Drain an Site - Simple Surface Model

Surface or open drainage is most often used to eliminate the effects of precipitation in time. It is a specially dug shallow individual ditches or a network of them. They are dug in places where moisture accumulates, and should slope into the lower part of the site. The bottom and walls of the drainage drain are well compacted. When it rains, water will run down the ditch.

Surface drainage is often combined with storm water drainage. The latter can be equipped with one of the types of water collectors:

1. Point. They are placed in certain places (under the gutter, near street taps).
2. Linear. These are trays located on a large area, but with a slight slope, and combined with each other.

Features of the arrangement of a closed drainage system

Closed or deep drainage provides for the construction of an entire pipeline from pipes located underground. This method is often used in areas to drain the area as the drain is not visible.

To lay deep drainage:

• along the perimeter and area of ​​the site, dig trenches with a depth of at least 30 cm and a slope of 2 cm per meter;
• combine them into a single system with a connection at the point of water discharge;
• at the lowest point, dig a drainage well, where water will drain;
• install a reservoir to collect water;
• fill small gravel on the bottom of the trenches;
• lay geofabric on top of the gravel so that it goes onto the walls;
• pour a layer of large rubble on top;
• lay pipes on crushed stone;
• install inspection wells in places of turns;
• fill pipes with medium gravel;
• cover with geotextile and sprinkle sand on top with a layer of up to 15 cm.

If necessary, the remaining trench space is covered with soil in order to level it with the soil surface.

Backfill drainage system

This is a less expensive option for deep drainage, but without the use of pipes. Its purpose is to drain the area after heavy rainfall and drain water from it. At the initial stage, the construction principle is similar to closed drainage. Ditches about 35 cm deep are also dug along the site at an angle (up to 3 cm for each running meter). Only instead of pipes they are filled with replaceable soil. They are material with high filtration properties - crushed stone, gravel.

In order for backfill drainage trenches to serve longer, their bottom and walls are concreted.

The side trenches should converge with the main one, and it, in turn, should be brought to the water intake. The latter should be located at the lowest point of the site. The bottom of the ditches is covered with geotextiles and only then filled with rubble.

Video on how to make a closed drainage system to drain the site