15 Jul 2014

Water rights, salinity management and remote sensing

[This long, useful guest post clarifies the inter-dependencies markets must consider.]

JD emailed me in response to this post on REAL water markets in California:
I think those markets are doomed without a (California) Constitution Change, as I understand it essentially says the State (the people of) owns all water, and only licenses its use to rights holders... that license is dependent on using it as the State values and -- needless to say -- (free) market forces are of little consideration to the State (unless it is explained to them by some special interest that doesn't want to be too bogged down by real free market forces!)

I’ve thought about it because salinization can only be controlled with return flows (i.e. any flows released to the environment) of sufficient quality and quantity. Salts need to be transported at low-enough concentrations that the environment is not trashed on the way and then deposited at a final (drainage) destination with adequate capacity. Current regulations often classify adequate return flows (especially if they draw on groundwater) as waste, meaning that the State may revoke the licenses of responsible dischargers.[1]

It wouldn't be so bad if the State allocated "surplus" to protect environmental return flows. Instead, it allocates the water to new homes or crops -- sometimes in a different hydrologic basin. Then they come back at the original user (who could have allocated appropriate return flows directly if it wasn’t considered a waste of water), who is tagged as a polluter since their release is now too strong to be assimilated into now-lower-volumes of water.

Which is why your idea of assuming all water use is consumptive absolutely must include the State defining and enforcing environmental flows to account for the need to assimilate and transport the residual wastes that inexorably result from approaching full consumptive use (i.e., 100% irrigation efficiency) and that cannot be kept out of natural systems (i.e., contained in a sewer or other dedicated waste collection system).

We are currently caught up in a water efficiency spiral to maximize consumptive use percentage that precisely parallels that which caused all prior irrigated agricultural societies to collapse due to salinization. They were very efficient but neglected return flows. Their ignorance is excusable, ours less so.
To this, I replied:
I agree, but I don't think it needs a constitutional change as much as a regulatory change. I also think return flows need to be incorporated into licenses.[2]
... and then JD replied:
You may be right (I’ve given up trying to understand water law rationally…especially the “right” to water) but regulators seem gun shy without clear direction from the top. I agree with you that free markets with transparent rules such as clear discharge standards and the ability to use their best resources towards meeting the standards are the most efficient, but if that freedom cannot be granted, then at least the State should not promulgate policy to trash the commons long term, for short term gains. I get it that some impacts to environmental flows may be reasonable in drought, but a free market would do better than "experts."

The return flows needs are variable (depending on the use), so it would make sense to license for a particular use. From a salinization perspective, the higher in the watershed and the more efficient the use (defined as maximizing consumptive use percentage), the higher the return flows must be, and they need to be properly allocated between ground and surface water. In many cases the surface water discharge can be reduced to zero so groundwater gets the return flows -- both to address quality of the aquifer (my primary concern here) as well as quantity.[3] An example of ways environmental flows could be incentivized is to give those who provide them an offset for a problematic discharge -- maybe even for a price -- be it captured storm water or any other water that can lawfully be used.
After reading this post, JD sent a further clarification:
Wow... just saw you link to the Chinese government using remote sensing to allocate water rights!

That’s the implementation I've had in mind to monitor salinization and groundwater overdraft. I recently read that wineries in the Napa area are using $2k drones for farm-level water management.

The implications are enormous. I understand from a colleague that satellite implementation costs the same whether for an acre or the entire Central Valley. If the State wishes to provide tools to manage both of the factors that will, if unchecked, destroy the groundwater resource, then it should collect and distribute data to the public in real time.[4] In theory, they could dispense with many of the expensive meters they are requiring agricultural users to install, and since 80+ percent of salinization is driven by ET, what better metric to deal with it -- free market or otherwise.
Bottom Line: Efficiency has limits, use water wisely.

  1. Caveats: Groundwater is a major reservoir whose use and quality must also be accounted for. Salt load is not the same as salinity because it's all about water use.
  2. [DZ here] JD has helped me see that my idea of assuming 100 percent consumption of licensed water will only work if environmental flows are not only excluded from those licensed diversions (my original idea) but ALSO specified to ensure that minimum return flows dilute salts and other contaminants that need to be "flushed."
  3. This is good in that things like nutrient/chemicals affecting surface water ecology are prevented at the source but bad on a salinization front in that the salts have no outlet and will accumulate in the soils and eventually the groundwater.
  4. A real time GIS type system remotely tracking evaporation and rainfall, coupled with flow and salinity quality data from the major reservoirs (i.e., water source) and some simple mass balance calculations can realistically provide the necessary insight to almost completely characterize the salinity management loads and mitigation needs for any area. This could be the necessary tool to provide transparent information to allow our (crowd sourced) civilization to avoid the fate of the ancient civilizations... if we pay attention.