Suggestions from Ben Ruddell

[jrising]

I have been meaning to get to these for over a year. From email correspondence:

• Could you use the economic production dataset that is part of NWED to validate the model? We have production and value of production, paired with water use and with trade.

• From my ERA paper in WRR in 2014, there are water exchange rates estimated (water in one county and its substitutability for water in another county). I wonder what your model would tell us about the water exchange rates, and how a policy of nationally leveling those exchange rates would affect production.

• I concur with the suggestion that removing constraints imposed by hydrological water balances or policies, and seeing whether that dramatically changes the optimal solution, is very intellectually interesting. I further suggest that it would be great to identify exactly how much water is "optimal", or approaching the optimal to 95% or 99%, in each county, region, etc.; this may or may not be more water than is available. It is also good to note which is the case (enough or not) in each location.

• Policies that are interesting to me include (1) the USDA's implicit policy of overproduction and net export of staple crops for national security purposes, (2) the USDA's other implicit policy of attempting to support and preserve rural farming communities and farming economies (no reduction in planted acreage in any given location over time), (3) Policies of groundwater sustainability vs. uncontrolled usage, with CA and AZ as operative examples, and (4) treaties that assign water rights in various ways.

• Examining the value of optimizing agriculture, and identifying policy or treaty barriers that prevent the optimal production, provides a basis for monetization of the removal of those barriers. For example, we could write a paper about how much money the various Colorado River Basin states should be paying each other to voluntarily release treaty water and increase overall agricultural production. We could apply the same concept to any bureau of reclamation project in the West. This might help the parties involved get un-stuck and actually negotiate a mutually beneficial solution to western water problems (and southeastern and plains problems...). It would be a very high impact paper, I think, if you don't mind getting calls from Senators.

• Another really interesting analysis would be to identify what the optimal physical water transfers would be, in a world where we could move water for free between any two counties in the USA but were still stuck with the national annual water budgets. This is a relaxed version of the no-water-budget constraints, releasing local fine-timescale water budget constraints but keeping the national water budget constraints at annual or greater timescales. Specific instances we'd look for would be (1) Northwest to Southwest transfers, (2) Great Lakes to South or Southwest transfers, (3) Mississippi River transfers to the same, (4) transfers to the front range from the west slope of the Rockies, (5) transfers from the Great Lakes to the Mississippi, and (6) the California and Arizona projects. 4-6 already exist to a great degree in Chicago and Denver, which makes them interesting examples. The New York pipeline is another example. What's a canal from Michigan to California worth?

• Another interesting scenario would be an energy transition where we reduced water demands for electricity and energy by various factors, by making greater use of renewables. How does the ongoing energy transition, or a hypothetical transition driven by national policy, affect the optimal agricultural production? What's the agricultural benefit?

• Optimal for whom? There are many parties who benefit from agriculture. The global market benefits, national security and tax bases benefit (and there are huge national costs that also exist in terms of subsidies), state or local governments benefit, farmers benefit directly, farm communities benefit indirectly. Do the optimal solutions differ depending on our objective function? Certainly they do, so what's the range of variation, which parties have aligned interests, who benefits or is harmed by increased or decreased production? This lets us identify the stakeholders on each side of the negotiation and estimate what's at state for each of them. This also lets us inform the design of markets that can grease the wheels for "globally" optimal decisions.

• I have discussed with Chris Lant at Utah State a CNH proposal for a project where we look at future climate and agricultural scenarios and determine how the water supplies will constrain or enable future transitions in production in the US, Canada, and Mexico. There is also an agent based and transportation infrastructure component to that work. We might consider using your model to address these questions. It would take a proposal. In the short term, however, the question for a paper would be, "Do we have the transportation infrastructure we need to enable this increased or optimized level of agricultural production?".

• Jim Heaney would be a great resource for Florida issues. I've already discussed with him the possibility of working on Florida and with Florida cities. He knows several of them pretty well.