The joint Torenthia-Caldris working group on the Toren River eastern tributary allocation reached provisional agreement on the dry-season minimum flow formula at its twelfth session, held in Aldenmere on Day 19 of Month 5. The formula governs the minimum volume of water the eastern tributary must carry across the border into Caldris during the April-through-September period, and has been the central technical dispute in renewal negotiations since the western tributary allocation was settled provisionally in Month 3 of Year 12.

The provisional agreement sets the dry-season floor at 62% of the ten-year rolling average flow, measured at the Aldenmere gauge station. The Caldris water authority had sought 68%; the Republic's technical team had proposed 58%. The 62% figure was reached through a joint hydrology assessment commissioned in Month 1 of this year, which established that the ten-year average understates the river's natural low-season baseline due to upstream infrastructure changes in Year 7 and Year 9. Both delegations accepted the adjusted baseline as the calculation reference.

What remains outstanding
The dispute resolution mechanism for years when annual rainfall projections fall below the agreed 30% threshold — years in which the 62% formula floor may itself be unsustainable. The Republic's position: the 30% threshold triggers a renegotiation window, not automatic formula suspension. Caldris's position: automatic suspension with a three-month review. The mechanism's design determines which party bears the risk in extreme low-rainfall years, and neither side has moved significantly on the underlying question since Month 9 of Year 12.

The LC's office confirmed the provisional formula agreement in a brief statement, noting that the framework team would meet again in Month 6 to address the outstanding dispute resolution mechanism. A spokesperson declined to characterize the likelihood of full framework agreement before the end of Legat Consul Rehn's term. Rehn himself did not appear at the Aldenmere session; the Republic's delegation was led by Deputy Chief of Treaty Affairs Aldric Solmen, who has been the working group's lead negotiator since Year 11.

The Caldris water authority issued its own statement, describing the provisional formula agreement as "substantive progress" and expressing hope that the Month 6 session would resolve the remaining mechanism question. The statement did not reference the Republic's upcoming change of government.

It is worth noting what the eastern tributary framework is and is not. It is a water allocation renewal — a technical agreement about volume, measurement, and baseline calculation. It is not a treaty under §3.6, which would require Senate ratification. It is an executive framework within the LC's existing treaty mandate, administered through the Toren River Commission established by the Year 4 treaty. The new Legat Consul will inherit the Commission, the framework process, and whatever state the dispute resolution mechanism is in at the time of the handover. If Rehn's team closes it before Month 9, the handover is clean. If not, the incoming LC's first working relationship with Caldris is defined by the outstanding item.