Causes and consequences of storm sewer clogging. Methods for cleaning open and closed systems. Methods for repairing an underground canal. Maintenance of the drainage main. The price of cleaning and repairing storm sewers.
Cleaning and repairing storm sewers is a set of measures to restore the functioning of the structure and prevent emergencies in the system. Such work is carried out regularly due to the inevitable obsolescence of parts and a large amount of dirt in the water. We learn about the methods of cleaning and repairing drainage systems of ground areas and roofs of houses from this article.
Features of the operation of storm sewers
In the photo, the clogging of the storm sewer
The storm sewer is designed to drain rainwater from the site. However, without constant maintenance, the system quickly becomes clogged with debris and ceases to perform its functions. Such troubles are found in all types of drainage, regardless of design.
Problems appear for the following reasons:
- A large amount of debris entering the gutters during precipitation and with melt water, therefore, most often they are clogged in the spring and during the season of heavy rains.
- Regular penetration of insects, small branches, sand, etc. into the pipes.
- Incorrect installation. The assembled system must comply with the requirements of SNiP 2.04.01-85. For example, pipes are laid with a slope of 2-7 mm / m towards the drain. If the slope is insufficient, the water flows slowly and leaves debris in the line. If the angle is too large, the liquid escapes without heavy dirt.
- A large number of sharp bends. Debris will accumulate at the bends.
- Consolidation of storm sewers with a common house. Too much solids and fat get into such a system. They mix and, after hardening, create a very tight plug that water cannot wash away.
- Construction work on the site. Styrofoam, shavings, plaster residues and other debris impenetrable for water may remain in gutters, trays, gutters.
Clogging of the storm sewer leads to the appearance of a large amount of water on the site, which has a bad effect on the environment:
- It can erode the foundation of a building, flood the basement, lead to waterlogging of the territory, etc.
- The accumulated dirt on the roofing system creates additional stress on the fasteners, which may not withstand and destroy the structure.
- Water overflowing the edge of the gutter hits the walls and ceiling and causes dampness in the room.
- Debris accumulates on the roof, under which it is always wet.
To clean the storm sewer, the following methods are used:
- Mechanical - the easiest option for open and closed systems. Dirt is removed manually or with simple tools.
- Hydrodynamic - debris is removed by a stream of water. For work, you will need special equipment that supplies moisture under high pressure to the pipeline.
- Thermal - a stream of hot water or superheated steam is directed into the clogged sewer.
- Chemical - for cleaning, special means are used that dissolve debris. They are harmful to the environment, so this method is used as a last resort.
When choosing a method for cleaning storm sewers, you can use the table below:
| Cleaning method | Terms of use | Features of use |
| Mechanical | For systems up to 100 m in length, 50-500 mm in diameter | Coiled cables |
| Hydrodynamic | For systems up to 50 m in length, 20-300 mm in diameter | High-pressure pumping equipment with special nozzles |
| Chemical | For pipes up to 50 m long, 20-300 mm in diameter | Technical cleaning agents, waste collection and filtration |
In practice, various methods are often combined to increase the cleaning efficiency, for example, mechanical with hydraulic or chemical with hydraulic.
Read more about how to make a storm drain
Storm sewer cleaning techniques
The choice of cleaning method depends on the type of storm sewer at home - open or closed. Open systems are easiest to clean - remove debris by hand or with simple tools and the structure is ready to go. Rebuilding underground pipelines is more difficult. Different technologies are used depending on the complexity of the congestion and operating conditions, often using sophisticated techniques. Popular congestion techniques are listed below.
Manual cleaning of open storm sewers
An open system often clogs up. garbage comes to it not only during precipitation, but also in dry weather. The problem is easy to identify visually - on the ground, water collects around the trays and forms large puddles. If the gutter is clogged on the roof of the house, the water is drained past the vertical gutter.
To clean the roofing system, you will need the following equipment: a ladder, a metal or plastic brush, a narrow scoop (the size of the gutter), a hose connected to the water supply. A scoop can be made from a plastic bottle. Plastic brushes are preferable, they do not damage the protective coating of the gutters. Telescopic brushes are helpful in cleaning long vertical gutters.
Cleaning an open storm water system is done as follows:
- Remove debris from the gutters, starting from the top of the roof. Collect it in a scoop and discard it in the bucket. Do not sweep dirt into drains.
- Inspect and clean the funnels that direct the streams downward. All gutters are equipped with a removable fine mesh that stops leaves and branches. All rubbish can be collected by hand.
- Remove dirt in vertical risers with a strong pressure of water from a hose. If there are various deposits on the walls, brush over them. It is recommended to carry out the work immediately after rain. wet layers are easier to remove.
- Remove debris deep in the pipe with a plumbing drill or cleaning tape. It is necessary to use a special tool carefully so as not to damage the protective coating of the system elements.
- Rinse the gutters and other elements of the storm drain with water and inspect the joints of the parts, where rust and leaks occur most often.
- Check that the gutters are securely fastened and their angle of inclination.
Start cleaning the ground part of the drain when you put in order the roof. Proceed like this:
- Remove the grates from the trays and remove debris with a shovel. If tiles are laid in the yard, there will always be a lot of sand in the recesses, which is washed out from the cracks between the fragments of the covering.
- Clean out gully and sand traps. If there are grease and oil filters in the system, flush or replace them.
- If the water from the storm sewer is disposed of through the filtering field into the ground, check it for the presence of silt. In case of a large amount of build-up, rinse the filter layer with clean water.
- On the path of water movement, a cascade of several grids is often created. They trap debris and need to be cleaned in time to keep the system running smoothly.
- For the maintenance of storm sewer treatment plants, you can use a garden vacuum cleaner, which quickly removes leaves from the grates on the trays and baskets of storm water inlets. In inconvenient places (for example, on the roof), a robot vacuum cleaner is used. It moves independently around the perimeter of the roof and removes dirt from the gutters with brushes. The device is powered by a battery.
Hydrodynamic cleaning of storm sewers
Clogged storm sewers are often caused by large amounts of sand and debris, creating tight plugs in the pipes. The most common method for cleaning underground areas is to supply high pressure water to the mains. The procedure can be conveniently performed using hydrodynamic devices on trucks. They are designed to service stormwater systems of any length and diameter. Short runs are washed with portable devices that fit in the trunk of a car.
The hydraulic devices are powered by a gasoline or electric engine. They are able to clean pipes with a diameter of up to 200 mm and a length of up to 40 m. The pump can supply water at a pressure of 200-500 bar.
Regardless of its capacity, all products have the following equipment:
- Power plant and pump;
- Capacity for water;
- Hose;
- Hose nozzle.
The kit may also include: a gun for supplying water under high pressure, tools for cleaning the nozzle, a frame with wheels for moving the device, pressure control devices, filters, etc.
The working tool of the device is a hose nozzle. It is selected depending on the diameter of the pipe, the degree of contamination of the route and other conditions. The nozzle has holes of various diameters directed at an angle of 15-45 degrees. Cleaning does not require a large amount of water - just 30 l / min. for pipes up to 300 mm in diameter.
Types of attachments for various tasks:
| Nozzle type | Appointment |
| Universal | Cleans lightly clogged lines |
| Rotary | Removes soft deposits - fats and oils |
| Donnaya | Removes silt and sand |
| Punchy | Breaks down dense and old congestion |
| Chain carousel | Removes tightly compressed debris |
Hydrodynamic flushing of storm sewers is performed in the following sequence:
- Attach the nozzle to the hose.
- Install it in the pipe and push it all the way.
- Connect the hose to the jetter.
- Turn on the device and supply water to the hose. To flush home systems, set the product to a pressure of no more than 150 atm. Sewer pipes will not withstand a greater pressure. The nozzles on the nozzle are directed towards the hose, so it automatically moves forward along the pipe under the action of the water flow. Due to the fact that the liquid comes out of the nozzles back, no pressure is created in the line that can destroy it.
- After passing the site, turn off the water and pull the hose back, collecting washed-out debris along the way.
- Cleaning ends with flushing the storm sewer, for which supply a large amount of water into the system. If the liquid does not come out well, repeat the procedure using the nozzle.
Read also how to make sewer ventilation.
Mechanical cleaning of storm sewers
The most affordable way to clean storm sewers is mechanical, in which debris is removed manually using the simplest tools. For these purposes, a cable is used, at one end of which a tip in the form of a spiral is attached, at the other - a handle for turning it. The purpose of the device is to make a hole in the mash through which process water can pass.
Install the cable into the pipe and move it as far as it will go. Then use a knob to turn it until the tip passes through the stopper. The passage of the blockage can be determined by the decrease in resistance when a load is applied. It is recommended to work together: one person twists the cable, the other directs it into the pipe. The tool must be removed periodically to remove debris. After punching the hole, feed a large amount of water into the system, which will wash out the plug.
There is also an improved version of the fixture, which has a drum instead of a handle. The tool allows you to remove debris from a pipe with a length of 7-10 m. Such devices, connected to an electric drive, are able to clean a pipe up to 30 m long.
If work is carried out in a storm sewer connected to a household one, after machining the pipes, it is recommended to additionally clean the pipes with superheated steam or boiling water. This removes fat deposits that cannot be washed off with cold water.
Chemical cleaning of storm sewers
Closed rainwater systems can cause blockages due to the mixing and hardening of large amounts of greasy waste and solid debris. Such a plug is removed with special chemical reagents, which are launched into the pipes. After a certain time, the cork dissolves and the contents can be washed out with a large number of inlets.
The mains made of plastic and cast iron are chemically cleaned. It is strictly forbidden to remove blockages in steel products in this way.
Observe the following rules when using chemicals:
- Use personal protective equipment to protect against burns and chemical fumes.
- Do not use reagents if the blockage exceeds 65% of the pipe. This can damage the rubber seals at the joints of the parts (if any).
- When preparing the solution, do not exceed the dose indicated in the instructions for the product.
- After use, collect the liquid in a separate container and clean it from reagents before disposal.
- Chemicals must be used with caution, they can cause contamination of the soil on the site and poisoning of groundwater. Therefore, it is necessary to use biochemical preparations for chemical cleaning.
Note! The method is intended for cleaning pipes with a diameter of up to 70 mm, the length of which does not exceed 4.5 m.
