The Supreme Court upheld an important Thurston Superior Court decision yesterday.  The court majority decided that new subdivisions must secure water supplies during the planning stages–that step to determine water adequacy cannot wait until houses are actually built.

This ruling makes logical sense.  It eliminates the possibility that developers might make significant upfront investments and suddenly find when it comes time to actually build houses, that no water is available.   The early timing of the determination eliminates potential conflicts between multiple water users, and between water users and instream flows.

The ruling will serve as a powerful new tool to protect our water resources from further over-appropriation.  This is especially true when this ruling is coupled with another recent decision from Kittitas County.  In that latter case, the Supreme Court ruled that securing a water supply involves more than determining how productive a well is.   The evaluation must also include a legal determination that senior water rights will not be impaired.

In sum:  when planning a subdivision, an early decision that water is legally available must be made.  The early and legal nature of the decision will protect both the financial investments of the developers and senior water rights including instream flows.

The decision in Knight v. City of Yelm can be found here.

The Kittitas decision can be found here (pdf file).