Urban water system basically depends on groundwater and reclaimed water supply, and engineering precipitation is the part of groundwater flowing out, and it will not stop day and night for a certain period of time.
Tap the main responsibility potential in the construction field, mobilize the subjective initiative of construction, design, construction and other units, and form the ideas of paying for water intake, sewage discharge, glorious water saving and shameful waste.
Each functional management unit shall formulate and strictly implement practical management methods according to the division of responsibilities and in combination with project characteristics, surrounding environment, nearby water systems and other factors.
Article 51 of the regulations of Shandong Province on water resources stipulates that for new, reconstructed and expanded construction projects, water-saving measures shall be prepared, water-saving facilities shall be constructed, designed, constructed and put into use simultaneously with the main project, and the normal operation of water-saving facilities shall be ensured.
According to the current situation of water reduction and drainage of infrastructure projects in the city, the government should issue corresponding system documents as soon as possible, clarify the relevant functional management units and management responsibilities, and urge all departments to perform their duties.
It is estimated that for a six storey residential building with simple structure, the construction of the main structure will take more than 2 months.
If the infrastructure precipitation can be supplied to urban water bodies in time and widely used in rivers and lakes, park waterscape, community water system, road cleaning, greening irrigation, etc., the problem of water-saving blind spot in engineering precipitation will be greatly improved..
If the extracted groundwater can be reasonably matched and fully used for urban production and life, it can be reduced by nearly 8 million m per year ³ The water supply is expected to save about 23 million yuan.
Referring to the technical specification for building foundation pit support (jgj120-2012), it is estimated that the total precipitation on the construction site in the five years is about 39.03 million cubic meters, and the average daily precipitation emission is 214 thousand cubic meters.
During the construction of the project, the dewatering and drainage shall be carried out continuously, and generally can not be stopped until the main structure of the building is completed.
The number of new buildings is increasing year by year, followed by a corresponding increase in construction precipitation.
At present, in the case of considerable shortage of water resources, is there a better choice for groundwater with good water quality, in addition to directly discharging into urban sewage pipelines or nearby natural water bodies? In this regard, the audit department has conducted more in-depth investigation and research.
In recent years, the total annual water consumption in the urban area of the city is about 25 million M ³， The groundwater to be discharged due to infrastructure construction is about 8 million m per year ³， It is equivalent to 1 / 3 of the annual water consumption in the urban area.
The survey found that almost all the groundwater extracted during the construction process was directly discharged into the sewage pipeline, which was basically not reasonably utilized, and the waste of water resources was very serious.
Click micro audit to pay attention to that water is the source of life.
At present, the city is in a period of rapid economic development.
First, strengthen the institutional restraint mechanism.
Second, stimulate the leading role of the market.
Then, the precipitation and drainage of the project may last for 2 months.
As we all know, in the construction process of construction projects, most of them will encounter underground aquifers.
The water shortage situation is very serious, and the per capita water resources is only 323m ³， Less than 1 / 6 of the national average.
Saving water and making rational use of water resources have become the consensus of the whole society.
In the section with rich water content, the groundwater permeability is 200m every day and night ³ Above all, even in areas with low water content, the groundwater permeability should reach 100m every day and night ³ above.
Third, give play to the role of comprehensive efficiency.
At the same time, an appropriate number of recharge wells can be designed in combination with the underground hydrological conditions and the distribution of surrounding projects to recharge the extracted groundwater to a deeper level to reduce the loss of groundwater; The construction unit shall play the main role of water intake responsibility, strictly implement the water reduction and drainage scheme, and formulate a detailed water use measure plan to fully apply the project precipitation to the construction sites such as concrete mixing, project maintenance, vehicle washing, dust reduction and watering, greening and watering, and try not to take tap water or dig another deep well for water if necessary.
This alone increases the financial subsidy fund by several million yuan every year.
At the same time, we should also strengthen the economic leverage of water resources fees, sewage treatment fees and water-saving incentives, so as to promote the effective solution of a series of problems related to water reduction, drainage and water saving in urban infrastructure projects.
The construction unit can guide the design and construction units to formulate reasonable water reduction, drainage and water use plans in combination with the nature of the project and the surrounding environment, and consciously pay various water resources fees; The design unit shall formulate a safe and reliable dewatering and drainage scheme according to the specific conditions of the project, and specify the number, depth and dewatering time of dewatering wells.
Article 4 of the comprehensive green building innovation award index system – key points for evaluation of water resources utilization issued by the Ministry of construction stipulates that the construction water-saving technology, water-saving equipment and facilities shall be adopted, and the reuse of water shall be considered as much as possible.
According to statistics, in the past five years, the total amount of water supply in the city’s urban area was 126.79 million cubic meters, and the total amount of sewage treatment was 193.22 million cubic meters, which was 1.5 times that of water supply; Among them, the sewage treatment capacity generated by production and domestic discharge is 107.77 million m3, and the remaining 85.44 million m3 of sewage treatment capacity is generated by building dewatering and drainage, rainwater mixed flow and other drainage factors, accounting for 44% of the total sewage discharge.
China is recognized by the United Nations as a country in short of water resources.
This year, the Municipal Audit Bureau complied with the needs of the development of the situation, organized an audit on the development and utilization of water resources in the city, paid special attention to the construction of water-saving cities, and carried out a special investigation on the water conservation and rational use of water in the city, especially the drainage and drainage of construction projects, in accordance with the requirements of research audit, The loss, waste and adverse effects caused by random discharge of dewatering and drainage are studied.
The audit believes that the flow direction and rational utilization of construction precipitation should be highly valued by leaders at all levels and relevant departments.
As the place where Dayu succeeded in controlling the flood, a city has an indissoluble bond with the water since ancient times.
At the same time, the dewatering and drainage of infrastructure projects has caused a huge increase in sewage treatment fees, with an average cost of 1.1 yuan / m ³， In order to reach the specified treatment concentration, after the mixed water of clean water and sewage enters the sewage treatment plant, a large number of chemicals need to be put into the sewage treatment plant for further treatment according to the procedures after man-made secondary pollution.
During the construction of construction projects, a large amount of groundwater will be generated and discharged, and most of the discharged groundwater will be directly discharged into the nearby urban sewage pipe network or nearby natural water bodies.
The audit found that with the continuous advancement of urbanization, the number of construction projects in the city is also increasing year by year.
Article 20 of the protection and management system for urban groundwater development and utilization issued by the Ministry of construction stipulates that various measures shall be taken to protect and manage groundwater resources, and natural recharge and artificial recharge measures shall be taken to supplement groundwater.
It is necessary to discharge the groundwater in time to reduce the groundwater level, so as to ensure the safety of construction structure and dry working environment.
All the sewage discharge costs are borne by the finance.
How to improve the refinement level of water-saving management and make full use of limited water resources has become an important issue related to the long-term development of Yucheng.
However, with the development of economy and the shortage of total water resources, the city has become a resource-based water shortage city.
In this regard, the audit suggested that relevant departments should strengthen the management of water reduction, drainage and water use of construction projects, make full reuse of construction precipitation resources, strengthen water conservancy law enforcement and inspection, and eliminate the waste of private drainage of construction precipitation.
By consulting the standing book of the construction permit of the city from 2016 to 2020, 938 new buildings and underground garages were added in the five years.
Therefore, the construction precipitation is directly discharged into the municipal sewage pipe network, which not only increases the treatment fee due to the low influent concentration of the sewage treatment plant, but also greatly increases the sewage treatment capacity, resulting in a double waste of financial funds of tens of millions of yuan.
Therefore, only one residential building with simple structure needs to discharge about 6000-12000 M ³ Groundwater, let alone high-rise buildings with complex structures.
