From 2065438 to June 2009, the rainfall in the urban area is 305 mm, which is 242.3 mm over the same period of the previous year, which is 26% more. Rainfall is scattered and regional. Among them, from 7: 00 to 20: 00 on August 1 day, there was a heavy rain in Zhengzhou. According to the statistics of the municipal meteorological department, the maximum hourly rainfall intensity in the city reached 70 mm that day, which was the maximum hourly rainfall intensity since Zhengzhou meteorological department started the hourly rainfall intensity monitoring work on 20 10, far exceeding the design drainage standard of the municipal pipe network in the city.
The aging of urban rainwater and sewage pipe network and low construction standard are one of the important reasons for urban road water accumulation. At present, the urban rainwater pipelines are 1.240 km, most of which are small in diameter and seriously aging. There are 1 60km for more than 20 years, and 1 to 360km for 20 years. The existing drainage facilities and drainage systems can not meet the practical needs of the rapid increase of urban population and rapid urban development.
At the same time, in recent years, due to the centralized construction of rail transit and various municipal public construction projects, various projects will cause different degrees of disturbance to the urban rainwater and sewage pipe network, resulting in the decline of drainage capacity of the pipe network.
In addition, the flood control standard of urban rivers is low. In the process of heavy rainfall, the water level of urban rivers is higher than the rainwater outlet, which forms the bottleneck of flood discharge, such as Jinshui River along the river, Lianhu East Road in Dongfeng Canal and Zhongzhou Avenue Airport Expressway in Qilihe River. Some residential areas and buildings do not distinguish between rain and sewage, and the sewage from rainy roads above heavy rain turns out, which also increases the collection and discharge pressure of urban road rainwater pipe network.
Zhengzhou will start dredging and reconstruction of open channels and peripheral rivers;
In response to the above problems, the urban management department also organized special personnel to inspect and supervise the progress of rectification of hidden water accumulation points and track the rectification effect of responsible units. This year, * * * issued 1 1 rectification notices, issued a list of flood control responsibilities for 745 hidden dangers and key areas and parts, and installed management responsibility publicity boards for 2 10 key hidden dangers. All responsible units have successively rectified 49 hidden dangers of water accumulation points through engineering measures such as laying drainage pipes, reforming branch pipes and adding collecting wells.
For the hidden danger points of stagnant water without engineering measures, the urban flood control office requires all responsible units to speed up the discharge of stagnant water through management measures such as pumping and drainage, diversion, guarding by special personnel and opening collecting wells. For those who do not drain water and affect traffic, it is clearly required to release the information of network disconnection in time, and coordinate the traffic police department to send special personnel to conduct on-site guidance to ensure the safety of citizens' travel. According to incomplete statistics, before the flood season, a total of 374 kilometers of rainwater pipes, open ditches 14 kilometers, more than 60,000 wells and nearly 55,000 sets of inspection wells were excavated in the urban area.
In the near future, the urban flood control department will centralize and unify the deployment of flood control materials vehicles, increase the number of mobile pump trucks or pumps, organize more personnel to dredge the collecting wells again, open the collecting wells as large as possible before the flood season, install protective frames, arrange special personnel to be on duty, and do emergency rescue work as soon as possible.
In terms of long-term measures, Zhengzhou will start dredging and reconstruction of open channels in open ditches, including peripheral rivers, promote urban river regulation, raise flood control standards, implement municipal pipe network construction and reconstruction with high standards, and further increase the promotion of rain and sewage diversion. At the same time, we will strive to use three years, relying on the construction of smart cities in our city, and comprehensively applying technologies such as Internet of Things, big data and mobile Internet to initially realize intelligent monitoring of urban rainwater and sewage pipe networks, rivers and key areas, so as to make all kinds of hidden dangers more timely.