Groundwater Control and Dewatering Methods

• Overview

The handling of groundwater is among the most complex of all construction problems. Controlling groundwater at construction excavations can be a critical matter when groundwater halts construction jobs or threatens bankruptcy of the project. Groundwater management falls into two major categories, either handling the groundwater before it enters the excavation or handling it after it enters the excavation. The decision to do one or the other or both is the most important decision to make for the project and requires diligent investigation of the jobsite soil conditions.

Authors

Agenda

Overview of Construction Dewatering/Groundwater Control?

• What Is Dewatering?
• What Does Dewatering Do?
• Origins of Dewatering
• Dilemmas That Arise From Improper Dewatering and Some Resulting Consequences That Can Occur

Widely Used Dewatering Methods

• Wellpoint System
• Deep Well System
• Eductor System
• Sumping/Open Pumping
• Temporary and Permanent Dewatering Systems
• Details of a Dewatering System

Things to Consider When Selecting a Dewatering System for Your Project

• Size and Depth of Your Excavation
• Location and Environment
• Proximity of Existing Structures
• Existence of Any On-Site Contamination
• Soil Characteristics/Subsurface Conditions
• Aquifer Characteristics
• Construction Schedule

Dewatering Case Studies

• Saluda Dam, Columbia, South Carolina - Eductor Dewatering Method
• Paddy Creek Dam, Morganton, North Carolina - Eductor Dewatering Method
• Batchtown Wildlife Refuge, St. Louis, Missouri - Deep Well Method
• New Madrid Pumping Station, New Madrid, Missouri - Deep Well Method
• Riverpoint West Street Improvement Project, Des Moines, Iowa - Wellpoint Method
• Pearland Town, Center Houston, Texas - Wellpoint Method
• Lake Fork Pumping Station, Dallas, Texas - Deep Well Method and Wellpoint Method
• Crystal River Power Plant, Crystal River, Florida - Sumping Method