Japanese knotweed excavation and disposal

At SE Knotweed, excavation removal digs out a Japanese knotweed stand and the surrounding contaminated soil, which is then taken off site under a waste duty of care. It is the fastest method and the one chosen when a plot must be clear quickly.

Excavation and disposal typically costs between roughly £4,000 and £12,000, driven by the volume of contaminated soil and access for machinery, and we confirm the figure at survey.

What is excavation removal?

Excavation removal is the physical extraction of a knotweed stand and its rhizome, digging to the depth and spread the survey has mapped so no viable root is left behind. The material is loaded and taken off site, and the ground is left ready for reinstatement.

It is a groundworks operation planned to a method statement, part of the wider knotweed removal service.

When is excavation the right method?

Excavation is the right method when a site must be clear fast, when a development or sale cannot wait for a herbicide programme, or when the ground is being dug for building work anyway.

It costs more than treatment because of the soil volume and the licensed disposal, so it is chosen for speed and certainty rather than economy. Get in touch to arrange a survey.

How much does excavation cost?

Excavation and disposal typically costs between roughly £4,000 and £12,000 for a domestic garden, and more on larger or awkward sites. The cost is driven by how much soil is classed as contaminated, machinery access, and the gate fee at the licensed facility.

We measure the stand at survey and give a fixed figure, so please read the range as indicative.

How long does it take?

Most domestic excavations are completed within a few days once the dig is scheduled, compared with the 3 to 5 seasons a herbicide programme runs.

The site is then available for reinstatement or building work straight away, which is the practical reason developers favour it.

What happens to the excavated soil?

Knotweed-contaminated soil is controlled waste, so it is handled under the Environmental Protection Act 1990 duty of care. It is carried by a registered waste carrier, tracked on a waste transfer note, and taken to a licensed facility.

You receive the paperwork, which a solicitor or lender may ask to see.

Is excavation guaranteed?

Excavation carried out by an audited specialist is backed by an insurance-backed guarantee, the same document a lender accepts for a treatment plan.

Because the rhizome is physically removed rather than killed in place, regrowth risk is low, and the guarantee covers the site should any viable material have been missed.

Common questions

Is excavation better than herbicide treatment?
It is faster and clears the site at once, but it costs more because of the soil volume and licensed disposal. Herbicide treatment is cheaper and slower. The right choice depends on your timescale and whether the soil can stay on the plot.
Where does the contaminated soil go?
To a licensed facility, carried by a registered waste carrier and tracked on a waste transfer note under the duty of care in the Environmental Protection Act 1990.

Book a survey and get a costed plan

Tell us the address and what a surveyor flagged. We confirm the plant, record the RICS category and set out the figures.

Book a survey
Call 01924 944600