How are storm water inlets arranged for storm sewers

Stormwater inlets for storm sewers perform the function of collecting surface water and transferring it to the main pipe. Thanks to them, garbage does not enter the system, and rain and melt runoff is sent to the sewer network. Such devices are also installed at enterprises for the removal of conditionally clean water generated as a result of industrial activity.

The device and dimensions of storm inlets

Installations for receiving water can be square, rectangular and round. They consist of the following parts:

• grates for screening out debris, protecting pedestrians from injury and landscape decoration;
• a water inlet with a basket for directing the liquid to the waste system;
• siphon partitions;
• a sand trap filtering small debris.

Usually, the devices are sold with all additional parts, but you can buy only a water intake chamber and complete the device yourself.

The sizes of rainwater inlets differ depending on the purpose and shape. The standard version is a cube with sides of 300 or 400 mm. The sidewalls are provided with branch pipes for connection to highways with a cross section from 110 to 200 mm. Cubic and other rectangular models can be installed anywhere where a stormwater well is located.

The round type of storm water inlets is more difficult to install, since it is not so easy to dig a pit of this shape.

To remove liquid from highways, storm inlets in the form of curbs are sometimes used. They fit perfectly into the road structure and are not subject to pressure from passing vehicles.

Varieties of rainwater structures

Products are classified according to the permissible load. Each type is marked with a specific letter:

The dimensions and weight of the device depend on the load class. The most durable structures are reinforced concrete and cast iron. Such rainwater collectors can weigh up to several tons.

Manufacturing materials

Structures made from ductile iron are heavy, but they are durable and not afraid of increased loads.

Other advantages of products made from this material include:

• resistance to sudden temperature changes;
• high throughput;
• resistance to aggressive chemical influences.

Cast iron products are coated with a special anti-corrosion compound, so they practically do not rust. They are made in accordance with GOST and are marked with DB, DK and DM, which stands for a large, round and small storm water inlet, respectively.

Concrete structures are erected in areas where a lot of pressure acts on the surface. Lightweight versions with 2 cm wall thickness are suitable for installation under gutters in factories. They are connected to the main system with plastic bends.

Highways require heavy devices with thicker walls. They are made of fiber-reinforced concrete. The most durable, made of reinforced concrete with a cast iron lattice, are able to constantly withstand the weight of special equipment and even aircraft.

On home gardens, cast iron and concrete structures are not often used. They are more expensive, because of their high weight, they require professional installation using lifting equipment. For private needs, it is more rational to use a plastic version of the storm water inlet. Such structures are quite durable, not subject to corrosion, you can install them yourself.

Smooth surface avoids blockages and increases throughput. The use of special stiffeners in polymer products increases resistance to stress.

All polymer devices are made with a liquid outlet pointing downward or to the side. From above they are covered with plastic or metal gratings.

There are also polymer concrete and polymer sand structures. They have the virtues of plastic and concrete products - they are strong, but they do not weigh much. However, such devices are superior in price.

Storm water inlets made of stainless and galvanized steel are used mainly in industrial enterprises where strict observance of sanitary and hygienic standards is required. They are quite expensive and are not able to withstand the pressure held by cast iron or reinforced concrete.

Criteria for choosing a storm water inlet

When selecting a storm water inlet of the required type for storm sewers, it is necessary to take into account various factors that ensure the reliability of the structure and a long service life.

Before buying, you should analyze how abundant precipitation is in the area where the water collector will be installed. They also take into account how much area the storm drain will take, the likely load on the surface and the cross-country ability of vehicles. Features of the landscape and climatic conditions are important.

The following requirements are imposed on the storm inlet itself:

• correspondence of the throughput to the amount of precipitation in the area where it will be installed;
• resistance to aggressive environmental influences and mechanical deformation;
• high anti-corrosion qualities.

On the personal plot of a small household, it is recommended to install a plastic storm drain. But if the territory is large, and there is a lot of precipitation in the area, or a transport entrance is equipped in a low-lying place, you should prefer the cast-iron or concrete option.

An important criterion for choosing a device is its cost. It depends on the material of manufacture, product size, configuration and manufacturer. Universal plastic rainwater collectors of different brands with identical dimensions 300 × 300 × 300 mm vary greatly:

• Hydrogroup - 357 rubles;
• "Hydrolica" - 550 rubles;
• Aquastock - 835 rubles;
• "Standartpark" - 1530 rubles.

The last option is at a price equal to the most inexpensive cast-iron storm water inlets. Concrete devices cost from 3000 rubles.

Installation rules

First of all, you need to determine the place to install the storm water inlet. If placed incorrectly, most of the sedimentary water will remain on the surface. To avoid this, drainage structures are mounted in the lowest areas of the terrain, or depressions are created for them, so that the streams themselves tend to the storm receiver. Similarly, install the devices under the gutters, while mounting them so that the water jet hits exactly the center of the grate.

Storm water inlets, which have a small weight and dimensions, can be assembled with your own hands. To do this, proceed according to step-by-step instructions:

1. Measure the depth of the storm inlet and add 400 mm to the resulting figure. They also measure the length and width and add 30 mm to each indicator.
2. According to the resulting dimensions, a pit is dug.
3. Sand is poured into the bottom of the pit with a layer of 10 cm, filled with water and carefully tamped.
4. The rainwater receiver is connected to the sewage mains that lead to the collector device.
5. Align the structure in height.
6. A concrete screed is poured onto the sand layer and the water intake tank is lowered there so that it sits tightly.
7. The concrete mixture is carefully poured into the slots on the sides of the structure.
8. Install a siphon partition and a water intake basket.

When the arrangement of the structure is completed, the gaps on the surface between the coating and the drainage device are covered with a gravel-sand mixture and refined with concrete or paving slabs.

The rainwater system must be looked after, otherwise it will clog up, which will make the entire storm sewer ineffective. Maintenance consists in cleaning the rain basket, grate and sand trap. Such procedures are carried out every two months.

If all the work on the installation of the stormwater receiver is performed correctly and it is regularly maintained, the sewer drains will not become clogged, the system will last more than half a century.