In the past few days, there have been widespread rainstorms across the country. There is no shortage of wanderings to see the sea in Wuhan, and the humorous view of Beijing Guan Waterfall. How many people in the legendary Noah's Ark can escape the floods and beasts? !

Today's topic: urban drainage system drainage system, sewerage system Drainage collection, transportation, water treatment and discharge of facilities in a certain way to form a combination of the overall. The general term for all levels of drainage ditch (pipe) roads and buildings used for removing waterlogging, preventing stains and salt. It is mainly composed of field drainage regulating nets, drainage sewers at various levels, lakes for storage, drainage gates, drainage pumping stations and drainage capacity-relief areas.

The purpose of the drainage system:
1. Longitudinal and horizontal drainage and permeable water of the expressway;
2. Vertical and horizontal drainage on the backside and side ditch of various retaining walls of highways;
3. Drainage of tunnels and underground passages;
4. Water supply and drainage of municipal works, water purification plants, sewage plants, garbage dumps, etc.;
5. Drainage of green areas such as golf courses, sports fields, and parks;
6. Development of slope soil and water conservation on slopes;
7. Underground drainage of site preparation works.

On a sunny day, the drainage systems that have been “behind the scenes” are rarely known. When we really need them to be independent, how does our urban drainage system perform? And look at a message from Northern Net:

The following content from the Northern Network:
A rainy day in the city "North drift" The capital's drainage system is resistant to much rain
A large city like Beijing has a huge drainage system. According to data from the Beijing Water Authority, as of the end of 2009, there were 5,227 km of underground drainage networks in the eight districts of Beijing City, which is equivalent to the distance from Beijing to Urumqi.
At present, road drainage in urban areas of Beijing is generally on the order of 1 to 2 years. In key areas, it is the case of 3 to 5 years. Overpass rainwater pumping stations are designed once every 2 to 3 years. Compared with the river flood control standards that are often heard in the “several decades” or even the “hundred-year” case, the urban road drainage standard may be puzzling.
Experts explained that urban road drainage standards and river flood control standards are not an algorithm. The "one-to-two-year encounter" of urban road drainage refers to rainfall, and the "one-on-a-decade encounter" of river flood control refers to hydrological flow, which are two different standards.
According to information provided by the Beijing Municipal Water Affairs Bureau, Beijing's urban drainage system standards are not high. If the “one-year-on-one” standard is converted into rainfall, Beijing’s urban drainage facilities will not experience particularly serious water accumulation in heavy rain of 30 mm/50 mm/h. However, if the rain falls to 50-70 mm per hour storm level, there may be some short-term accumulation of stagnant water and water.

Observation: Preventing Urban Awkwardness, Our Law is Blank
As netizens ridicule, every summer, we will find that, in fact, the most talented person in the city is the water supply and drainage professional. Why is it that the major cities that are bright in appearance are hard to bear the weight of rain?
The drainage system of foreign cities, New York is based on the "one-fifteen-year-old" standard; Tokyo is based on the "five to ten years once met" standard. In China, Beijing generally follows the "one-to-two-year meeting" standard, Wuhan is built according to the "one-on-one-on-one" standard, and the urban drainage systems of Hangzhou and Nanchang are also "little horse-drawn carts" and drainage standards. Seriously lags behind.
In some developed countries, the prevention of urban crimes has already risen to the height of law. For example, the legal system for the prevention of urban rampant crimes in the United States provides very detailed regulations for the prevention and control of urban internal crimes; Germany has the “Insurance Insurance for Urban Internal Liability”, which not only reduces the government’s flood control burden and pressure, but also cultivates citizens’ awareness of flood protection; The "Sewerage Act" has strict regulations on the drainage capacity and various technical indicators of the sewer. In China, although there is also a "Flood Prevention Act," it is almost a blank in preventing urban floods.
What is the reason why the drainage system encounters defects? The "Voice of China" observer, Professor Zhang Qichen, believes that because the underground drainage system is not a face project, many cities have neglected supervision and planning.

All in all, a heavy rain test the body and mind of the majority of people, but also tested the city's drainage system, do not let the drainage become the pain of the city!