What are the key technical points for the design and construction of landscaping water supply and drainage systems?

The landscaping water supply and drainage system is the core infrastructure of landscaping projects, directly related to the growth and survival of green plants, the long-term maintenance of landscape effects, and the rational utilization of water resources. Its scientific design and standardized construction are key to ensuring the quality of landscaping projects and achieving the unity of ecological and landscape benefits. The landscaping water supply and drainage system covers two core modules: the water supply system and the drainage system. The design and construction need to be combined with the green layout, plant species, topography, climate conditions, and surrounding municipal pipe network conditions, following the principles of scientific adaptation, energy conservation and environmental protection, and long-term stability. Strictly implement various technical points to avoid problems such as poor water supply and drainage, water resource waste, and pipe network damage. Based on industry standards and engineering practices such as the "Construction and Acceptance Specification for Landscape Greening Engineering" (CJJ/T 82-2012) and the "Design Standard for Outdoor Water Supply" (GB 50013-2019), the design and construction technical points of landscape greening water supply and drainage systems are centered around the four core stages of design, construction, quality inspection, and post management. Each stage is coordinated and connected to build an efficient, energy-saving, and stable landscape greening water supply and drainage system.
The design and construction of the landscaping water supply and drainage system follow the core principles of "adapting to local conditions, adapting to needs, prioritizing water conservation, and ecological environmental protection". The core goal is to achieve precise water supply, smooth and orderly drainage, balance water resource utilization efficiency and landscape ecological needs, ensure reasonable irrigation of green plants, and avoid the impact of accumulated water on plant growth, landscape effects, and surrounding environment. Design and construction should take into account both technical expertise and on-site adaptability, combined with the functional requirements and plant growth characteristics of different green areas, to optimize targeted solutions and ensure stable system operation and convenient maintenance.

The key technical points for the design of garden greening water supply system are to achieve "precise water supply, water conservation and high efficiency", focusing on four aspects: water supply mode selection, pipe network layout, irrigation method design and hydraulic calculation, to ensure that the water supply system is accurately adapted to the needs of greening and environmental conditions.

The water supply method should be selected based on the scale of greening, the conditions of the surrounding municipal pipeline network, and the water resources situation. Small scale landscaping can be directly connected to the municipal water supply network for water supply, while large-scale landscaping can adopt a joint water supply method of "municipal pipeline network+self provided water source". The self provided water source should meet the irrigation water quality standards and avoid using water sources containing pollutants and harmful impurities. The selection of water supply methods should balance reliability and economy, ensuring stable water supply while reducing water resource waste. The layout of the pipeline network should follow the principles of "reasonable layout, shortest pipeline, and easy maintenance", combined with the division of green terrain and plant planting areas. The main, branch, and branch pipes should be reasonably arranged to avoid pipeline intersections and detours, and reduce pipeline losses. The layout of the pipeline network should avoid the green core area, areas with dense plant roots, and areas with dense underground pipelines to prevent damage to plant growth and the pipeline network caused by later construction and maintenance.

The design of irrigation methods should be based on plant species, planting density, and the functions of green areas. Water saving and efficient irrigation methods should be selected, with priority given to drip irrigation, micro sprinkler irrigation, and other water-saving irrigation technologies to reduce water resource waste caused by flood irrigation and sprinkler irrigation. Drip irrigation can be used in areas with trees and shrubs to accurately supply root water; Lawn and ground cover plant areas can be treated with micro sprinkler irrigation to achieve uniform irrigation; Large squares and landscape green spaces can use sprinkler irrigation to balance irrigation and landscape effects. The design of irrigation systems requires the installation of auxiliary facilities such as control valves, filters, and pressure gauges. Filters are used to remove impurities from the water source and prevent blockages in irrigation pipelines; Control valves are used for zone controlled irrigation, facilitating maintenance and management. Hydraulic calculation is the core of water supply system design, which requires accurate calculation of pipe network flow and water pressure to ensure that the water pressure and quantity in each irrigation area meet the irrigation needs of plants, avoid problems such as insufficient water pressure and uneven flow, and control the flow rate of the pipe network to prevent erosion and damage.

The key technical points for the design of garden greening drainage system are to achieve "smooth drainage, flood prevention and accumulation prevention", focusing on four aspects: drainage method selection, pipe network layout, slope control, and rainwater utilization, ensuring timely discharge of rainwater and excess irrigation water in the green area, and avoiding plant root rot and soil compaction caused by water accumulation.

The drainage method should be selected based on the terrain, soil texture, and green layout. Common drainage methods include surface drainage, underground drainage, and mixed drainage. In areas with flat terrain and good soil permeability, surface drainage can be used by setting up drainage ditches and slopes to guide rainwater to naturally flow into the municipal drainage network; In areas with low-lying terrain, poor soil permeability, or high groundwater levels, underground drainage should be used, and facilities such as drainage blind pipes and infiltration ditches should be installed to drain the accumulated groundwater; Large scale landscaping can adopt a mixed drainage method, combining surface drainage and underground drainage to ensure drainage effectiveness. The layout of the pipeline network should be staggered with the water supply pipeline network to avoid mutual interference. The drainage pipeline network should be connected to the municipal drainage pipeline network to ensure smooth drainage. At the same time, facilities such as inspection wells and sedimentation tanks should be set up. Inspection wells are used for pipeline maintenance and dredging, while sedimentation tanks are used for settling rainwater and sediment in irrigation water to prevent blockage of the drainage pipeline network.

Slope control is the key to drainage system design, and the slope of surface drainage should be controlled within 0.3% -5% to ensure rapid flow of rainwater and avoid water accumulation; The slope of underground drainage blind pipes and infiltration ditches should be controlled at 0.5% -2% to ensure smooth drainage of underground water. The design of rainwater utilization should follow the principle of "ecological priority and circular utilization". Rainwater collection pools can be set up in green areas to collect rainwater for irrigation and reduce municipal water consumption. At the same time, permeable paving and rainwater gardens can be laid in green spaces to enhance rainwater infiltration capacity, supplement groundwater, and achieve water resource recycling.

The key points of construction technology for garden greening water supply and drainage system must strictly follow the design scheme and industry standards, focusing on the three core links of pipe network construction, irrigation and drainage facility installation, and backfilling and compaction, to ensure that the construction quality meets the standards and the system operates stably.

The construction of the pipeline network requires on-site laying out first, accurately positioning the pipeline direction and inspection well position according to the design drawings. After laying out, trench excavation should be carried out, and the depth and width of the trench excavation should meet the design requirements. During the excavation process, it is necessary to avoid disturbing the surrounding soil and plant roots. If underground pipelines or obstacles are encountered, the pipeline layout should be adjusted in a timely manner. After the excavation of the trench is completed, the bottom of the trench needs to be leveled and compacted, and a cushion layer should be laid. The cushion layer should be made of sand and gravel, with a thickness controlled between 10-15cm, to ensure that the trench bottom is flat and solid, and to prevent settlement and damage to the pipeline network. Pipe network pipes shall be made of materials with corrosion resistance, aging resistance and strong compression resistance. Common pipes include PE pipes, PVC pipes, cast iron pipes, etc. After entering the site, the pipes shall be sampled for re inspection, and the specifications, models and quality certificates shall be checked. Unqualified pipes shall not be put into use.

The pipe network connection needs to be operated in a standardized manner. PE pipes are connected by hot melt, PVC pipes are connected by adhesive, and cast iron pipes are connected by socket. The connection parts should be sealed tightly to avoid water leakage. After the installation of the pipeline network is completed, a water pressure test (for the water supply pipeline) and a water filling test (for the drainage pipeline) need to be conducted. The water pressure test pressure for the water supply pipeline is 1.5 times the design pressure, and it is considered qualified if there is no leakage or pressure drop after stabilizing for 30 minutes; The water filling test of the drainage pipeline must ensure that the pipeline has no leakage and the drainage is smooth. The installation of irrigation and drainage facilities requires precise positioning, controlling the installation position and height of valves, filters, nozzles, blind drainage pipes, and other facilities to ensure normal operation of the facilities. The installation of nozzles should be evenly distributed to ensure full coverage of the irrigation area; Blind drainage pipes and infiltration ditches need to be laid flat and wrapped with permeable geotextile to prevent sedimentation.

Backfilling and compaction must be carried out after the pipeline network test is qualified. Backfilling soil should be selected from soil that is free of debris and has good permeability. Backfilling and compaction should be carried out layer by layer, with a backfill thickness controlled between 20-30cm and a compaction coefficient of not less than 0.95, to avoid settlement and damage to the pipeline network caused by insufficient compaction of the backfill soil. During the backfilling process, it is necessary to protect the pipeline network and facilities to avoid collision and compression. After the backfilling is completed, the site needs to be organized and the green landscape restored.

Quality inspection is a key link in ensuring the design and construction quality of the water supply and drainage system. It needs to be carried out throughout the entire design and construction process, with a focus on testing the sealing of the pipeline network, water pressure, drainage effect, and installation accuracy of facilities. During the design phase, it is necessary to review the hydraulic calculations and pipeline layout to ensure that the design scheme meets the regulatory requirements; During the construction phase, it is necessary to conduct on-site inspections on the quality of pipes, connection quality, trench excavation, backfilling and compaction, and promptly identify and rectify quality hazards.

The sealing test of the pipeline network is achieved through water pressure test and water filling test to ensure no leakage; Water pressure testing must ensure that the water supply pressure and flow rate meet the design requirements; The drainage effect detection needs to be carried out on rainy days or under simulated irrigation conditions to check whether the drainage is smooth and there is no water accumulation; The accuracy testing of facility installation requires checking the installation position and height of facilities such as nozzles, valves, and inspection wells to ensure compliance with design standards. The parts that fail the inspection need to be repaired and rectified in a timely manner until they pass the inspection.

Post maintenance is an important guarantee for maintaining the long-term and stable operation of the landscaping water supply and drainage system. The technical points revolve around three aspects: pipe network maintenance, facility maintenance, and water quality management. The maintenance of the pipeline network requires regular dredging and cleaning of the water supply and drainage pipeline network, especially the drainage pipeline network. It is necessary to regularly clean the sediment and debris in the inspection wells and sedimentation tanks to prevent pipeline blockage; If damage or leakage is found in the pipeline network, it needs to be repaired and replaced in a timely manner. Facility maintenance requires regular inspection of the operating status of control valves, filters, nozzles, blind drainage pipes, and other facilities. Damaged facilities should be repaired and replaced in a timely manner to ensure their normal operation.

Water quality management requires regular testing of irrigation water sources to ensure compliance with irrigation standards and avoid using polluted water sources to irrigate plants; For rainwater collection tanks, it is necessary to regularly clean the debris and sediment inside the tank to prevent water quality deterioration. At the same time, it is necessary to adjust the irrigation water volume and frequency according to seasonal changes and plant growth needs, in order to achieve water-saving irrigation.

The technical points of the design and construction of the landscaping water supply and drainage system run through the entire process of the project, and each link is interrelated and indispensable. It is necessary to strictly follow relevant industry standards, optimize the design plan based on the actual situation of the greening project, and strengthen construction technology control. With the application of water-saving technology and intelligent equipment, the design and construction of garden greening water supply and drainage systems are developing towards refinement, energy conservation, and intelligence. Strictly implementing various technical points can not only ensure the healthy growth of green plants and improve landscape effects, but also achieve the rational utilization of water resources, promoting the development of garden greening projects towards ecological and sustainable directions.