5 Ways to Control Groundwater During Excavation

Say goodbye to groundwater on large construction sites.

Controlling groundwater during excavation is extremely important in the construction industry. Dewatering helps provide temporary reductions in groundwater levels for structures that must extend below groundwater level. There are a variety of dewatering and groundwater control methods used on major construction sites and in this blog we’ll outline a few of the more popular methods.

Different methods of Groundwater control and dewatering

1. Sump pumping – The most basic form of groundwater control is sump pumping, which is simply a method where groundwater is collected using a sump and pumped away from the construction site. This type of groundwater control can be inexpensive, but ground loss as well as excessive seepage can be time consuming and expensive to deal with. Pre-drainage methods may be used for situations where sump pumping may pose a threat to the instability of the ground or adjacent structures.

2. Wellpoint systems – These are used to lower groundwater levels and help provide safe working conditions during excavation. Wellpoint systems consist of a number of small diameter wells, which are connected with a header pipe to a wellpoint pump. The wellpoint pump then creates a vacuum that draws water up from the ground.

3. Siphon draining – works by pumping water by gravity along siphon pipes. Siphon draining is most often used where there are unstable slopes. Wells are typically installed in or above the unstable zone of a slope and are then pumped using siphons that utilize the natural slope of the area.

4. Deep well systems – consist of a number of bored wells, each using a submersible borehole pump. As water is pumped from each well, the groundwater is lowered creating a cone of depression.

5. Ejector systems – Similar to deep well systems, ejector systems are based on wells which lower the groundwater level to provide safe working conditions. Ejectors utilize air in the wells to create a vacuum that draws water out of the soil.

Various factors such as soil type and the nature of the construction site will effect the type of dewatering method that will be ideal for your project.

Importance of expert advice

No matter the size of your excavation site, the experienced team at MWI Pumps can help guide you through the process of determining the most cost effective and reliable dewatering solution.

We offer a variety of trash pumps, submersible pumps, and wellpoint systems depending on your groundwater control needs. Reach out to our team today at 954-426-1500 to discuss your project with one of our experienced team members.