A recent visit to the site of the greening of the parks project in six ans revealed an interesting phenomenon: in the early stages of construction, many project managers did not pay much attention to the drilling of the wells and were always trying to find any construction team, which tended to cost a lot of money later. According to statistics from the greening of the san city parks association in 2023, the proportion of local gardening wells that were scrapped by irregular construction was as high as 15 per cent, with direct economic losses exceeding $20 million。
I. Real gap between professional drilling and general construction teams
In a 200-acre eco-agriculture park project in the six anguan district, the owner initially selected a general construction team and committed to completing four 120-metre deep wells in 15 days. As a result, the drill was stuck in a 50-metre geological fragmentation zone until day 8, and the construction team lacked professional processing experience, which eventually led to the fracture of the rig. Not only was the work period delayed by one month, but the additional maintenance costs were up to $80,000。
Also in the quan district, another horticultural project, carried out by the six angji drilling wells, was successfully completed using a specialized aerodynamic pore hammer process, by adjusting the slurry ratio and drill parameters when encountered with similar shreds. Ultimately, it takes 12 days, three days ahead of the projected schedule, and the quality of the water produced has been tested to meet the water standards of the landscape。
Recommendations:
Before signing a contract, check the construction party's drilling cases for almost three years
Request for a geotechnical survey report, rather than an empirical study
Clarification of construction process descriptions, in particular treatment of different layers of gravel, clay, etc., common in the six ant
Ii. Three key parameters for well design to consider
Many owners consider drilling to be “deeping a pit, laying a root tube” and do not consider the effects of later use. According to the greening water well design guidelines issued by the san city water authority in 2022, the formal well design requires attention to three core indicators: unit surge, sand content and well wall stability。
In the example of the landscape lake project in a villa six, the project party initially designed a well at a depth of only 80 metres, which was considered sufficient to supplement the volume of artificial lakes. Following a field survey by the gishun drilling team, an average annual reduction of 1. 2 metres in the groundwater table in the region was observed, and it was recommended that the depth be adjusted to 120 metres and that the location and diameter of the filtering pipe be optimized. After delivery, wells are maintained at 80 cubic metres of water per day to meet the needs of the project, despite a continuous high temperature of 40 days of drought。
Recommendations:
Specialized survey commissioned from hydrogeologically qualified units at a cost of about $3,000-$8,000
10-15 per cent deep redundancy, based on regional long-term hydrological observations
Detailed structure of wells, including key parameters such as the location of water filters, gravel filling specifications, is required from the construction party
The “holes” in the terms of the contract should be clear
In a municipal greening project in the six antananarivo region, the owner's contract provided for “guarantee of water discharge”, but there were no clear water quantity and quality standards. As a result, wells were released, but only 20 cubic metres per day, far from meeting the irrigation requirements of 150 acres of green land. More problematic is the fact that water contains up to 3 per cent of sand, resulting in the complete drip irrigation system being blocked。
When carrying on such projects, ji-soon drilling wells are expressly agreed in the contract that no less than 50 cubic metres/hour of water per unit surge containing less than 100,000 sands and that water quality meets the water quality criteria for landscape water (gb/t 18921-2019). At the same time, a vertical bias of not more than 1 per cent for drilling boreholes was promised and a third-party test report was produced。
Recommendations:
The contract must contain three rigid indicators of quantity, quality and solubility
Agreed acceptance process: 24-hour continuous water pumping test followed by water sample inspection
Guarantee period: not less than two years recommended, covering all facilities such as pumps, pipes, wells, etc
The selection of drilling teams is based on the “four-eye” principle
In the course of the study, i summarized the method of selecting a qualified drilling team, known within the industry as the “four look” principle:
At least two different types of rigs, such as a soft layer of land for the san region, need to be equipped with a positive cycle drill, or with an air submersible drill when it comes to hard rock. The gishun well, with 14 sets of equipment ranging from 100 to 300, can cope with a variety of complex geological features。
A qualified drilling team must be staffed by registered geologists, hydrogeologists and security officers. There had been low-cost drilling by project owners at a cost of $600/m, with the result that the construction personnel had no basic ground recognition, and the rig had ended up 60 metres。
(iii) previous performance: constructioners are required to provide contracts and acceptance reports for similar projects for almost three years. More than 200 landscaping projects have been completed in the jishun wells in san, including many landmark works such as the six ann central park and the moon island wetlands park。
Post-sales services: professional drilling teams will provide 2-year quality assurance and 24-hour emergency response services. There was a project at 2 a. M. Where the pump malfunctioned and the jishun drilling team arrived at the site within 40 minutes, avoiding widespread drought of the green plants。
The greening of the parks project is ushering in a new phase of development, with wells as the “heart” of infrastructure, which, while accounting for only 3-5 per cent of the total project cost, have a direct impact on plant survival and landscape performance. It would be better to find a professional team and spend every penny on a knife than to spend money in the future. After all, a reliable well not only saves water resources, but also guarantees the long-term operation of the project。
