with a rainwater inlet grate.Open type rainwater drainage.

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In 1881, the first major works on the improvement of the city began in Gatchina, and in 1884, the main construction works on the first sewerage and water supply networks were completed, which continued until 1988. Since 1890, the central water supply system began to operate for the first time. However, the precedents of using rainwater drainage for other purposes, enshrined in law, contributed to the fact that wooden structures (made mainly of slabwood) did not cope in such conditions, since they had cracks and quickly rotted from the discharged sewage from the toilets, turning rainwater british student data wells into cesspools, which led to an environmental disaster.

Classification
Closed type rainwater drainage system

Depending on the method of drainage of atmospheric water, there are three types of storm sewerage:

open type (ditch system) - water is diverted using open channels and trays to the nearest collector or directly to a reservoir. Sometimes water is diverted to forests, plantations and other sparsely populated places.
closed type - flowing rainwater is collected by drainage channels included in the construction of roads and sidewalks, and through special wells (rain inlets) enters a network of underground pipelines, through which it is diverted to the nearest thalwegs, natural reservoirs or to treatment facilities, directly or through a collector. In some systems, water is diverted into an impermeable hatch, from where it is then pumped out by a sewage truck.
mixed type - some elements of the open network are replaced by closed underground pipelines. This is the most common system.
Treatment facilities
In most large cities, water from storm drains enters treatment facilities. As a rule, separate treatment facilities for storm drains are not built. The water enters existing treatment facilities, and after purification, it is sent to a natural reservoir or water body.

Ditch drainage system
The open-type ditch system is used in cities and is multifunctional in its meaning. It performs two main functions of its purpose: as an irrigation network, through which urban green spaces are irrigated, and as a drainage network, it performs the function of draining rain and storm water from atmospheric precipitation from the surface of the streets. It consists of special concrete ditch trays, which are installed along streets and roads. Ditch trays usually have special drainage holes through which some of the water is absorbed into the soil.