Percolation Testing Tavistock

To determine if a site in Tavistock is suitable for a drainage field or soakaway, a percolation test is conducted to measure the soil's ability to absorb water, which is crucial for septic tank or surface water management. 

We carry out Percolation tests, they are crucial for ensuring proper drainage field design and compliance with Building Regulations, specifically Approved Document H (Water). 

Percolation tests assess the soil's ability to absorb water, vital for septic tanks and sewage treatment plants.  

We carry out percolation tests for soakaways for storm water.

Why are Percolation Tests Necessary? 

• Building Regulations (Approved Document H):Building Regulations, particularly Approved Document H, stipulate that drainage fields must be designed and constructed to ensure effective and safe disposal of wastewater.
• General Binding Rules: set of rules to meet in order to install a drainage system
• Soil Permeability: Percolation tests determine the soil's permeability, or its ability to allow water to drain away, which is essential for the proper functioning of drainage systems.
• Drainage Field Design: The results of percolation tests are used to design the size and depth of drainage fields to ensure they can handle the wastewater flow effectively.
• Groundwater Protection: Percolation tests help assess the risk of groundwater contamination from improperly designed drainage systems.
• Trial Site Assessment Hole: Before undertaking a percolation test, you will first need to carry out a Groundwater Source Protection Zone search and a Trial Site Assessment Hole, which will allow you to fully inspect and assess the groundwater table within your site.

How Percolation Tests Work:

• Test Holes: Percolation tests involve digging test holes at the intended depth of the drainage field.
• Water Filling: The test holes are filled with water and the time it takes for the water to drain away is measured.
• Percolation Rate Calculation: The percolation rate, which is the speed at which water drains away, is calculated from the test results.
• Design Considerations: The percolation rate is used to determine the required size and spacing of drainage field components, such as soakaway chambers or drainage pipes.

Key Considerations for Percolation Tests:

• Minimum Distances: Drainage fields must be located at a minimum distance from buildings, watercourses, and water supplies.
• Water Table: The bottom of the drainage field must be a certain distance above the water table to ensure proper drainage.
• Soil Type: The type of soil plays a crucial role in determining the percolation rate and the suitability of the site for a drainage field. 
• Professional Advice: It's advisable to consult Walkhampton Drainage Company for guidance on carrying out percolation tests and interpreting the results.
• Soakaway Regulations: Soakaways must be designed and installed to have sufficient storage capacity, to prevent the collected surface water from backing up and over-flowing (flooding) at gullies close to the building, during heavy rainstorms and rapid snowmelt events.
• Percolation Test for Soakaway: A soakaway test is required to determine if a new or replacement soakaway can be installed for disposing of surface run-off water. A Percolation Test is required where a septic tank or sewage treatment plant is proposed for treating foul water.