Vance Kennedy: Put a price on groundwater, coming and going

Our backup water source – groundwater – should be treated as an asset that is charged for when used and is paid for when added to. Treat it as a market.

When we have a severe drought, there is not nearly enough surface water to go around, and groundwater becomes extremely valuable. That’s why we need to encourage keeping our aquifers recharged, or full.

Who is responsible for recharging the aquifers? The major source of recharge – or putting water into the aquifers – is flood irrigation by farmers. A significant second source is river infiltration, and the least important is rainfall.

Who is responsible for the use of groundwater? That list includes all electric ratepayers, including industry, cities and farmers using drip irrigation. They should be charged for the amount of groundwater used.

Since flood-irrigating farmers on permeable soils are the major source for groundwater recharge, they should be paid for the water they allow to reach the aquifers – or at least not charged for it. Such an approach will discourage drip irrigation, encourage flood irrigation and also encourage conservation by cities. Admittedly, it will be a challenge to determine what fraction of flood-irrigation water recharges the aquifers, but some studies have looked at the problem already.

More and more farmers are going to drip irrigation. It is convenient and requires relatively little labor, once installed.

I understand that one government agency actively encourages that practice because it conserves water. But there are definite negatives not usually recognized. Drip irrigation often uses groundwater instead of contributing to it.

That groundwater contains salts not found in snowmelt, which is used for flood irrigation. Over time, those salts can accumulate in the soils and destroy their structure, reducing soil fertility.

Looking ahead, global warming is expected to reduce snowpack in the mountains and possibly greatly increase the intensity of rainfall. That means groundwater storage is going to become even more important. But vertical infiltration is slow, especially on lesser soils. Hence, it is important that a maximum area of permeable soils – ground the water can pass through with relative ease – be kept for groundwater recharge through farming.

Of the three absolute requirements for life – water, food, air – water is important for its own sake and also for food production. It is imperative that we change our past habits and take a new look at our way of doing things.

This story was originally published November 17, 2014 at 4:21 PM with the headline "Vance Kennedy: Put a price on groundwater, coming and going."