Dewatering is an artificial process that involves extraction and removal of excess groundwater from the soil typically a construction site. The idea behind dewatering is to lower the groundwater level to a point that it is safe for construction activities such as building foundations, elevator shafts, piers, etc. to take place. Typically, this process involves fitting and installation of dewatering equipment like pumps adjacent to the site and drawing water through wells.
During a construction dewatering and treatment project, the groundwater recovered often contains contaminants that must be treated. This can either be done through temporary or long-term groundwater remediation systems before the water is safely discharged. However, dewatering process involves a host of environmental impacts and therefore, a comprehensive assessment of the ground to be dewatered should be done. This is an important stage in construction projects where a feasibility study is conducted to identify potential construction problems and plan mitigation strategies.
During the dewatering assessment stage, there are few issues that need to be addressed before shovels break ground. They include:
Project Timeline
As with other projects, construction dewatering and treatment operation must be guided by a strict time frame that allows smooth running of processes. There has to be a commencement date that determines the exact time and date dewatering process should begin. In this stage, duration, quality, and frequency of the dewatering discharge are estimated. This allows for prior groundwater management.
Profiling The Groundwater and the Excavation Area
Through scientific analysis, proper assessment of the groundwater can be done to ascertain the quality as well as the contaminants inside. Furthermore, this process enlightens the contractor on the nature of the water table in question together with the surrounding soil profile. In addition, understanding the vegetation and the structures around the dewatering site prepares the project for any eventualities. The ground profile, on the other hand, will help determine whether the soil contains iron pyrites, which is a toxic substance that should not be allowed on the environment. In most cases, when the groundwater is acidic, additional and effective measures are introduced before the water is brought off the ground.
Viability of the Dewater Treatment
There are various groundwater remediation methods that can be used during dewatering treatment. But depending on nature of the excavated water, different approaches can be used to make the water safe for different end-use. Some of the common dewater treatment options include pH adjustment, settling, filtration, chemical flocculation among others.
Baseline Assessment
Analysis of the recovering environment will help the construction to understand water table levels, the flow of water throughout the season as well as water quantities. This step is crucial in determining the most efficient construction dewatering and treatment systems to be used.
Confinment with the Land Laws
This is probably the important stage during assessment stage. It’s at this stage that the dewatering project gets to be approved or rejected by the relevant authorities. However, it is important that you notify the council, which speaks for the people and get to hear their views.
