Japanese knotweed eradication

Japanese knotweed eradication demands its complete removal. Contaminated material may be removed from site to a licensed landfill site or disposed of on site. Methods used are reliable, swift and cost effective solutions. However, do note that these methods are more expensive than Japanese knotweed control methods.

Japanese knotweed eradication may be achieved by:

Japanese knotweed removal 'Dig and dump'

Full excavation of the Japanese knotweed.

Full excavation on site and root barrier to site boundary. Backfilling with clean material.

Although a more expensive option, costs may be controlled and readily justified when correctly managed. Commonly used on development sites but used elsewhere in some specific circumstances. Contaminated areas are fully and completely excavated (often to 1.8m depth but shallower or deeper depths may be required). Knotweed rhizomes [underground shoots] spread up to 7m in any direction so the excavated area may be much more extensive than the surface growth suggests.

Contaminated material is all taken to licensed landfill sites for disposal using cost effective methods that The Knotweed Company will advise for use to its clients. Risks will be assessed prior to commencing excavations and managed using comprehensive Method Statements and Risk Assessments. Only fully qualified staff members that hold the relevant Construction Site Certificates of Safety (CSCS) or Construction Plant Certificate of Safety (CPCS) will carry out this work.

Costs will depend upon location, quantities, site history and other factors that may vary from £5000.00 to £millions of pounds (all prices exclude VAT).

All methods must be individually priced. Control measures for smaller infestations of knotweed may be discussed on the telephone but site visits are normally arranged and more detailed quotations offered.

Site visits are normally not charged but, due to the expertise of this company, full technical reporting in some instances, may require an agreed charge with the client before that visit.

On site burial

Cell – clean material being deposited on top of capping root barrier.

Full excavation of the Japanese knotweed area as made as above but, instead of removing it from site, the knotweed material is buried on site. The burial 'cell' may need to be fully or partly lined with root barriers and have a minimum of 2m of clean soil or other fill material on top. Permission to use this method must be gained by consulting with the Environment Agency but, as the material is dealt with on site, may also qualify for tax concessions.

'Cells' are typically 4m deep and constructed with battered sides to ensure stability.

Risks will be assessed prior to commencing excavations and managed using comprehensive Method Statements and Risk Assessments. Only fully qualified staff members that hold the relevant Construction Site Certificates of Safety (CSCS) or Construction Plant Certificate of Safety (CPCS) will carry out this work.

Costs will depend upon location, quantities, site history and other factors that may vary from £5000.00 to £millions of pounds (all prices exclude VAT).

All methods must be individually priced. Control measures for smaller infestations of knotweed may be discussed on the telephone but site visits are normally arranged and more detailed quotations offered.

Site visits are normally not charged but, due to the expertise of this company, full technical reporting in some instances, may require an agreed charge with the client before that visit.

Removal of contaminated material and encapsulation on site of the remaining area

Excavation to reduced level in progress.

Root barrier being installed.

Clean imported top soil spread over the root barrier, ready for turf to be laid.

Some - or even the majority of the Japanese knotweed contaminated soil - is removed from site and a root barrier used to encapsulate on site the remaining Japanese knotweed rhizomes. These 'hybrid' methods use reduced level excavation and root barriers extended to completely encapsulate the remaining knotweed rhizomes before being installed into deeper trenches around the perimeter.

Risks will be assessed prior to commencing excavations and managed using comprehensive Method Statements and Risk Assessments. Only fully qualified staff members that hold the relevant Construction Site Certificates of Safety (CSCS) or Construction Plant Certificate of Safety (CPCS) will carry out this work.

Costs will depend upon location, quantities, site history and other factors that may vary from £5000.00 to £millions of pounds (all prices exclude VAT).

All methods must be individually priced. Control measures for smaller infestations of knotweed may be discussed on the telephone but site visits are normally arranged and more detailed quotations offered.

Site visits are normally not charged but, due to the expertise of this company, full technical reporting in some instances, may require an agreed charge with the client before that visit.