Phasing a survey budget across two financial years

Seasonal survey work does not respect your financial year. If the planning application is going in next autumn, the ecology visits that support it start in April, the traffic counts sit in neutral months either side of the summer holidays, and the invoices land in two different budget years. Phasing a survey budget is mostly a matter of deciding which spend has to be committed before 31 March and which can wait, because a missed survey window costs far more than the survey.

The rule of thumb that holds on most sites: commission in the autumn for the following spring, and treat the survey programme as a fixed constraint the rest of the programme works around.

Why seasonally constrained work splits across years

Most ecological survey windows open between March and September. Breeding birds run from March to August. Bat emergence surveys run from May to September, with the best results between May and August. Great crested newt environmental DNA sampling has a short statutory window in spring, and trapping surveys run from mid-March. Reptiles are surveyed from April to October, with the best results in spring and early autumn. Botanical survey work needs plants in growth, roughly April to September.

Transport data has its own calendar. Traffic counts want neutral months, which in practice means avoiding August and the weeks around Christmas, and parking surveys following the established overnight and weekend methodology avoid school holidays for the same reason.

Put those together and a site that needs bats, newts, botanical and traffic data has commitments running from March through to October, with reporting into November. If the application is going in during the following January, the spend straddles two financial years whatever you do.

Which surveys commit spend early

The distinction that matters to a budget is between work that is instructed early and work that can be held.

A Preliminary Ecological Appraisal is the item to fund first in any year, because it tells you which of the expensive seasonal items you actually need. Funding it in March, so that the report lands in early April, is usually better value than saving it for the new budget.

The real cost of a missed window against a delayed start

Compare two numbers honestly. A repeat season of bat surveys on a modest site is a known, quotable figure. A twelve-month delay to a scheme carries land holding costs, professional fee inflation, the risk that the development plan or national policy moves under you, and in some cases the loss of an option agreement.

On most residential schemes the delay cost is an order of magnitude larger than the survey cost, which is why finance teams usually agree to commit seasonal survey spend before the year end once the comparison is set out. Put it in writing with both figures. That is a much easier conversation than asking for a variation in July.

There is one case where waiting is right: where the scheme itself is unsettled and the survey scope would change with the layout. Surveying the wrong red line is a pure loss.

Staging instructions to control risk

Instruct in stages with clear gates, so that each release of spend follows a decision.

1. Desk study and preliminary appraisal, with a scoping note naming the surveys needed and their windows.
2. Programme and budget paper, showing the spend by financial year and the decision dates.
3. Season one instruction, covering the surveys whose windows open first.
4. Interim review after the first visits, because presence or absence changes the rest.
5. Season two or supplementary instruction, including any repeat visits.
6. Reporting and metric completion, which can sit in the following budget year.

The interim review is the gate people leave out. Finding a roost in the first emergence survey changes the licensing route, the mitigation design and the cost, and that is the moment to revise the budget rather than at the end.

Contingency for repeat visits, and where to put it

Build contingency at the survey line, not the project line. Weather losses are ordinary: a cold, wet May pushes bat surveys later and can force a repeat where conditions failed the guidance criteria. Detector failures happen. Access refusals from a neighbouring landowner stop a transect.

A contingency of a reasonable percentage of the ecology line, held by the project manager and released against a stated reason, is the arrangement that survives audit. Say what triggers it: failed weather criteria, an unexpected protected species, an extension of the red line, or a consultee asking for an additional visit.

Programme contingency matters as much as money. If the survey programme ends in October and submission is planned for November, there is no room for the repeat visit you may need. Two to three weeks of float between the last survey and the submission date is the minimum worth having.

Reporting spend against the programme

A single table, updated monthly, does the job: the survey, its window, the instruction date, the committed value, the value invoiced, the budget year it falls in, and the status. Circulate it with the programme rather than separately, because the questions the board asks are about the date, not the invoice.

Watch two dates that move costs between years. Planning application fees are indexed annually from 1 April, so a submission slipping from March to April pays the new figure, and the current schedule should be checked rather than assumed. And the Biodiversity Net Gain Assessment is completed against the version of the statutory metric current at the time, so a version change between seasons means the metric is rerun. That is a small cost with an annoying habit of arriving late.

Approvals to secure before the season opens

Work backwards from the first window. To have surveyors on site in the first week of April you need the instruction placed in February, the fee proposal in January, and the budget approval in December. Land access agreements take longer than anyone expects, particularly where a tenant farmer is involved, and no surveyor will trespass for you.

The approvals worth having in hand before March:

• signed access agreements for every parcel, including third-party land needed for transects
• appointment of the ecologist and the transport consultant, with the scope covering repeat visits
• a decision on the red line, because it defines the survey area
• board or lender approval for the full seasonal commitment, not one visit at a time

Our notes on traffic counts in neutral months and botanical survey season set out the individual windows in more detail.

Browse all 66 PlanScope report types and start a draft at the report index to see which documents your scheme needs before you set the budget.

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