What to watch at the Basin Water Summit in Port Alder: shared data, drought rules and the falling Ilvar

Six governments meet in Port Alder from Monday. A data-sharing protocol looks within reach; whether countries agree in advance how to cut river withdrawals in a drought is the open question.

Learn these first and the rest of the story reads easily. Press a term to ask a follow-up question.

a.low flow

The smallest volume of water passing a river gauge over a period, often the August minimum in the Basin.4Delta Hydrology ReviewIlvar summer low flow has fallen by a third since 2022Specialist · 3 Nov, 16:15

b.allocation

An agreed share of a river's water that each country or user may withdraw.5Kesh Daily CourierKesh backs data sharing but not binding allocationReported journalism · 3 Nov, 21:1510The Lantern ReviewA binding plan would freeze today's map of who uses the riverAnalysis / commentary · 4 Nov, 18:05

c.drought trigger

A pre-agreed measurement, such as flow at a gauge, that sets off planned cuts in withdrawals.6The Valdorian HeraldValdoria to press for shared drought rules on the IlvarReported journalism · 4 Nov, 00:357Northgate Policy InstituteAgreeing drought cuts before the drought is the only time it worksAnalysis / commentary · 4 Nov, 05:35

d.data protocol

An agreement on how often, in what format and with whom river measurements are shared.2Meridian WireSummit agenda: river data, drought plans and the IlvarWire · 3 Nov, 02:55

• Sabine Kroll

  Environment Minister of Valdoria

  Will propose pre-agreed drought cuts on the Ilvar.6The Valdorian HeraldValdoria to press for shared drought rules on the IlvarReported journalism · 4 Nov, 00:35

• Taro Venn

  Environment Minister of the Kesh Federation

  Leads the Kesh delegation; backs data sharing, opposes binding allocation.5Kesh Daily CourierKesh backs data sharing but not binding allocationReported journalism · 3 Nov, 21:15

• Merovan foreign ministry

  Organisation

  Host of the summit.1Port Alder GazetteSix governments confirm delegations for Basin Water SummitReported journalism · 2 Nov, 20:15

• Saranth Water and Hazards Agency

  Organisation

  Statutory monitoring body presenting lake and glacier data.3Saranth Water and Hazards AgencyAgency to present Teyla Lake melt data at Port AlderPrimary / official · 3 Nov, 09:35

Background, from the study guide

1. 2010

   Lake baseline

   The year against which Teyla Lake's late-summer level is now compared.

2. 2022

   Ilvar at 410

   Lowest August flow at the Aldermere gauge is 410 cubic metres per second.

3. 2026

   Ilvar at 270

   The August low falls to 270, about a third below 2022.

4. 2026

   Teyla Lake record low

   The lake's late-summer level is 3.1 metres below its 2010 average.

5. Autumn 2026

   Port Alder summit

   Six governments meet to discuss data, drought plans and the Ilvar.

This story, update by update

1. 2 Nov, 20:15

   The Merovan foreign ministry confirms six ministerial delegations.1Port Alder GazetteSix governments confirm delegations for Basin Water SummitReported journalism · 2 Nov, 20:15

2. 3 Nov, 02:55

   Officials describe the agenda and the draft compact.2Meridian WireSummit agenda: river data, drought plans and the IlvarWire · 3 Nov, 02:55

3. 3 Nov, 09:35

   Saranth agency says it will present Teyla Lake data.3Saranth Water and Hazards AgencyAgency to present Teyla Lake melt data at Port AlderPrimary / official · 3 Nov, 09:35

4. 3 Nov, 16:15

   Delta Hydrology Review publishes Ilvar low-flow figures.4Delta Hydrology ReviewIlvar summer low flow has fallen by a third since 2022Specialist · 3 Nov, 16:15

5. 3 Nov, 21:15

   Kesh sets out its position on allocation.5Kesh Daily CourierKesh backs data sharing but not binding allocationReported journalism · 3 Nov, 21:15

6. 4 Nov, 00:35

   Valdoria says it will propose drought triggers.6The Valdorian HeraldValdoria to press for shared drought rules on the IlvarReported journalism · 4 Nov, 00:35

Of 6 key facts: 5 reported, 1 official statement.

• ?What flow level would trigger cuts under Valdoria's proposal, and how cuts would be shared.6The Valdorian HeraldValdoria to press for shared drought rules on the IlvarReported journalism · 4 Nov, 00:35
• ?Whether the draft compact will be put to a vote or issued as a chair's statement.2Meridian WireSummit agenda: river data, drought plans and the IlvarWire · 3 Nov, 02:55
• ?A campaigning channel claims the Kesh delegation has orders to walk out if drought rules go to a vote. It cites unnamed sources and has not been corroborated by any other source.9RiverWatch ChannelKesh will walk out if allocation is on the table, sources sayMonitored · 4 Nov, 15:35