Steve Knell is the general manager of the Oakdale Irrigation District. He’s an advocate of water sales outside the district, and has presided over the sale of 382,408 acre feet of water over the last decade.
Knell’s latest claims about groundwater suggest the problem of overdrafting has been exaggerated.
“In OID’s portion of Stanislaus County, our data show groundwater, on average, was 74 feet below the surface 10 years ago. Today, it’s at 88 feet. The underground resources beneath OID are falling about 1.4 feet per year (or roughly 15 feet over 10 years). That’s not a positive trend, and it’s one we need to address, but it’s not an “emergency” situation as has been the focus of many media reports.”
Knell then says that the water levels of seven of the wells monitored by the Oakdale Irrigation District have actually risen. Knell cites the rise in water levels as a sign there’s no need for “sweeping regulations that could limit pumping.”
Given the tremendous increase in usage of groundwater in the Oakdale Irrigation District in the last decade, Knell’s comments might seem to point to the need for more information about groundwater. But most any hydrologist could explain what’s going on.
The first question to ask about rising groundwater levels is, “Where does the water come from?” The easy answer is rainfall. But if there’s very little rainfall and water levels are still rising, what then could be the source of the higher water levels?
One answer is aquifers. Ordinarily, water in aquifers flows much more easily horizontally than vertically. However, when pumping lowers the water level of the aquifer near the pump, water from a higher elevation (adjacent aquifer) can flow in and raise the water table near the well.
Another answer to the conundrum of rising groundwater levels even during a drought is rivers, lakes, and reservoirs. Pumps near rivers, lakes, and reservoirs pull water horizontally from beneath those sources. The recent Scott River lawsuit featured studies that showed the relationship between pumping groundwater and reduced flows in the river.
Had those studies not been made, it might have been very easy for someone to say of groundwater levels near the Scott River, “It’s not an emergency situation.” The point is that when large volumes of groundwater are pumped and there’s little to no recharge from rainfall, snowmelt, or flood irrigation, there can’t be any effect but depletion of groundwater stores OR depletion of surface water sources, or both.
Knell’s motive for trying to minimize alarm about groundwater depletion is clear: He wants to sell water. The state of California and the federal government are very likely to require more water for fish and the Delta ecosystem from both the Stanislaus and Tuolumne Rivers. If the government requires increased flows for fish and the Delta ecosystem, Knell won’t be able to sell as much water.
Not only will there not be as much water to sell, the groundwater crisis will be highlighted when the general public realizes the connection between surface water and groundwater recharge. Steve Knell wants to sell water. Therefore, he’s trying to create an outcry against increased flows for fish and the Delta. It’s that simple.