A three-scenario oil and water forecast across five central processing facilities, with transfer line, facility and disposal limits applied to every well and each well counted once.
Outcome
Objective met4 of 4 success criteria. Read the conclusionThe northern half of the field feeds five central processing facilities. Two transfer lines, rated at 40 and 50 thousand barrels a day of liquid, let wells move between them. Management wanted to know how much oil the network could sustain each year to 2029 under three cases: no transfers, transfers only, and transfers with optimisation.
The existing spreadsheets could not answer it. They added the 50 thousand barrel liquid capacity to an oil total, counted moved wells at both facilities, and used a planned commissioning date as the date the line was available. The field total did not reconcile.
We built the forecast workbook from the operator's allocation export at one reference date. Every well carried a home facility, a current facility, blended oil and water rates, and a decline. Each scenario was a set of dated switches: facility oil and water limits (200 and 220 thousand barrels a day at facility A from the second quarter of 2027, 207 and 117 at B, 70 and 37 at C, 245 oil at D from the fourth quarter of 2027), transfer line liquid capacities of 40 and 50 thousand barrels a day, and the dates new tankage and water routes were assumed available.
The allocation logic applied every limit at the same time: liquid on the transfer line, oil and water at the receiving facility, and disposal downstream. A well appeared once. The output separated gross oil moved, net oil gained, oil deferred, water displaced and extra water generated. A validation sheet checked conservation of oil, water and gas across every move, double counting, limit breaches, switch dates and zero or missing wells. The workbook, a methodology note, a report and a management presentation were issued together from one number ledger.
At three of four facilities the water limit sits below the oil limit
Receiving-facility planning capacities for oil and produced water, four central processing facilities, with the dates each capacity was assumed available.
Source: forecast planning inputs, September 2026, operator withheld. Transfer lines between facilities assumed at 40 and 50 mbd liquid.
Management had a range by facility and by year instead of one number. The forecast showed that the second transfer line moved the binding limit from the sending facility's oil capacity to the receiving facility's water capacity. The recommendation was to bring the water treatment and disposal schedule forward and not to add transfer capacity.
The job was to give management a forecast to 2029 that reconciled and showed where the limit was. It did. The workbook closes to zero on conservation, each well is allocated once, and the three scenarios differ only by dated switches. The finding that water, not transfer capacity, binds at three of four facilities changed the order of the operator's project list.
| Success criterion | Met | How it was achieved |
|---|---|---|
| iOil, water and gas conserved across every transfer, checked to zero on the validation sheet | Met | All four checks pass on the issued workbook; the validation sheet is part of the deliverable |
| iiEvery well allocated to one facility in every month of every scenario | Met | Home and current facility carried on every well; the double-counting check on the validation sheet returns zero in every month of all three scenarios |
| iiiScenarios differ only by the declared switches, each with a date and a source | Met | Switch register issued with a date and a source for each facility limit, line capacity and availability date; the three scenarios share one base case |
| ivThe binding limit at each facility readable by year without opening the model | Met | Scenario tables to 2029 name the binding limit at each facility for each year, with capacities labelled as planning inputs dated September 2026 |
Deliverables
Evidence note
Work done for the operator of an onshore field in the Middle East. The client, the field and the facilities are not named. Capacities are planning assumptions from the forecast exercise, dated September 2026, not published operating limits.
A deferral register and weekly facility summaries that keep oil separate from liquid, transfers separate from net gains, and every item with an owner and a date.
Met4 of 4 success criteriaOperator engagementRead the caseNorth Sea·Producing assetIntegrated well, network and facilities modelling on a mature offshore asset, where the binding limit sat with a different team from the one reporting the loss.
Met3 of 3 success criteriaPractitioner experienceRead the caseNext case: A new 16-inch transfer line, from concept to first flow
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