Prepared and maintained by Cambridge Development Archaeology for development teams working across Cambridge and Cambridgeshire.
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The next decision
A watching brief is agreed monitoring, not unrestricted attendance or automatic clearance. Confirm the observed works, discovery protocol and reporting obligations before the groundworks window.
An attendance schedule that can be procured
List the operations requiring attendance, expected notice, safe access and named site contact. Price mobilisation, agreed attendance and reporting separately from additional instructed work; changes to the groundworks sequence can change attendance even if the site area stays the same.
The scheme should identify pause/notification authority, protection of discoveries and when extensive evidence requires a revised method. Record areas observed, inaccessible ground and the report’s limitations. The authority decides whether that evidence satisfies the condition.
- Cambridgeshire County Council: Archaeological advice for planning developments ↗
- UK Government: Historic environment planning guidance ↗
Content updated .
Define where monitoring ends and further work begins
A watching brief covers the agreed monitoring and recording scope. Discovery assessment, an instructed change in method and further excavation are separate decisions, not automatically unlimited attendance under the original price. Set out the notification and instruction route in the approved scheme and appointment so the groundworks team knows who can agree the next step.
What actually happens on site
An archaeologist attends agreed groundworks — topsoil strip, foundation trenches, service runs, attenuation basins — and records archaeological features as they are exposed by your plant. The agreed discovery protocol determines when works pause, how evidence is protected and when further advice or a changed method is needed.
The archaeologist works to an approved written scheme, keeps a site record, recovers finds, and produces a report afterwards. The presence is monitoring, not excavation: the intention is to capture information, not to strip and dig the site in advance.
When an authority will accept it
A watching brief is accepted where archaeological potential is real but low, or where the surviving remains are expected to be sparse, and where the development's ground disturbance is limited. It is a proportionate response to a modest risk.
- Small infill or single-plot sites within an existing settlement footprint
- Sites where evaluation has already been carried out and found little or nothing
- Limited groundworks — service corridors, extensions, individual buildings
- Previously developed land where earlier disturbance is documented
- Sites where the archaeological advisor's concern is specific and narrow, such as a single known feature
When it is the wrong instrument
On an open greenfield site with good archaeological potential, a watching brief is a commercial trap rather than a saving. If substantial remains appear during your groundworks, you are discovering them at the most expensive possible moment: plant on site, programme committed, and no agreed budget for excavation.
That is the scenario a prior evaluation is designed to prevent. On larger schemes we would rather argue for evaluation early — while the cost of being wrong is a survey, not a stoppage — than accept a watching brief that shifts risk into the construction phase.
Cost and programme effect
Watching brief cost is driven by attendance days, not by area. Intermittent attendance needs a defined day-rate and scope; its cost depends on notice, visits, findings and reporting. A continuous attendance across a long enabling-works programme is not, and it is worth agreeing in advance which operations genuinely require presence.
Programme effect is usually small, but it is not nil: the report and any finds work still have to be completed before the condition is discharged. Build that reporting period into your programme rather than discovering it at handover.
What the watching-brief scheme must settle before groundworks
The approved written scheme should remove ambiguity from the site instruction. It needs to identify the operations covered, the notice period, who can pause work, how exposed archaeology will be protected, the recording time available and what happens if the discovery exceeds the watching-brief scope.
A vague instruction to monitor all groundworks is difficult to programme and price. A plan that marks the relevant excavations and links them to the contractor's sequence lets attendance be booked around actual risk.
- Groundworks and site areas that require attendance
- Minimum notice for each visit and the daily site contact
- Safe access, plant control and how the archaeologist sees the formation level
- A stop-and-escalate protocol for significant or extensive remains
- Reporting, finds, archive and condition-discharge deliverables after attendance
How to procure it without buying open-ended attendance
Price the known attendance against the groundworks schedule and state the day rate for additional instructed attendance. Require daily records of areas observed and time used. This gives the developer cost control without forcing the archaeologist to under-allow for a changing contractor programme.
If attendance is likely to be continuous for weeks, revisit whether a watching brief is still the most efficient method. A short targeted evaluation can sometimes define and clear the risk before the main works begin.
What to send us
The condition wording, the site plan with your groundworks sequence, and any earlier archaeological work on the site. From those three we can say whether a watching brief is likely to be accepted, how many attendance days it realistically needs, and where the risk of a stoppage sits.