Among several pieces of encouraging news Peter Drekmeier brought the Stanislaus County Water Advisory Committee during his October 26 visit to Modesto was the scientific consensus that it’s still going to rain in the northern San Joaquin Valley. In fact, said Drekmeier, according to the best science we have, it’s probably going to rain just as much as it always has. The catch is that the realities of climate change mean it’s going to rain less often and, when it does rain, it’s going to rain much harder.
Drekmeier, a Palo Alto resident, is Policy Director for the Tuolumne River Trust. He’s sometimes found himself at odds with local farmers about the needs of salmon versus the needs of almond orchards, but he found a receptive audience when he spoke about the value of collaboration versus the costs of conflict.
San Francisco and Bay Area counties’ claims on their Tuolumne River water rights have conflicted with the needs of Valley farmers and residents for decades. During a short Power Point presentation, Drekmeier argued that it would benefit all parties, whether Bay Area residents or local farmers, if we could better control the flood and drought events which have become more common as climate change accelerates. There is widespread agreement among meteorologists, hydrologists, and geologists that more storage is a prime necessity for sustainable water use in the near future.
Whereas dams and reservoirs have been the traditional options for water storage and flood control in the past, there’s a growing consensus that groundwater recharge represents a far better choice for the onrushing needs brought about by climate change. Even if it weren’t forced upon Valley residents by requirements stemming from the Sustainable Groundwater Management Act (SGMA) of 2014, groundwater recharge and storage make especially good sense in Stanislaus County, where the eastern foothills feature soils uniquely suited for banking groundwater.
The black sands of the Mehrten Formation, a geologic feature of the east side of the Sacramento and northern San Joaquin Valleys, are highly permeable. In Stanislaus County, those black sands once held the last truly viable aquifer in the San Joaquin Valley, at least until thousands of acres of new orchards began tapping the groundwater reserves. Today, the aquifer is declining rapidly.
Citing statistics that show the City of San Francisco and other Bay Area Hetch Hetchy customers have reduced water usage from 293 million gallons per day thirty years ago to under 200 million gallons per day over the last eight years, Drekmeier suggested that the water gained from these conservation efforts could benefit both Bay Area and Stanislaus County residents. The benefits to both regions would come from recharging Stanislaus County groundwater reserves. The goal would be a sustainable water balance that would enable farming while providing an emergency “bank” of water for Bay Area residents during times of extreme drought.
Groundwater recharge and banking have already been explored on a small scale at various locations throughout the Valley. Given the proximity of the Stanislaus and Tuolumne Rivers to Stanislaus County’s eastern foothills, the opportunity for banking water in the Merhten Formation’s black sands during heavy rain events could offer tremendous benefits to fish, farmers, and urban and rural residents.
One major benefit would be greater control over the flows biologists say are necessary for sustainable salmon populations. Greater control in general would also benefit farmers, who would be able to count on more consistent water allocations from year to year.
Drekmeier suggested that collaboration between Stanislaus County and Bay Area water users would offer both regions greater water security as climate change presents new and pressing threats from floods and drought.
“We’re all in this together,” he said, as nodding heads around the room suggested a growing consensus that shared plans for banking water could promise a sustainable future where there’s enough for everyone, when and where it’s needed.
[…] Story continues […]
Good article. At least on Water issues , we mostly agree. Recently, I have heard and seen comments about Geo Engineering on a large scale that could be causing some of our drought conditions- seems some agencies have been employing this to deflect the sun’s rays, yet the ‘side effect’ could be less rain. But, the facts and the truth are always hidden somewhere….
Damon Woods:
Thank you, that is a very serious problem, if Geo Engineering on a large scale is causing some of our drought conditions. A good function of The Valley Citizen is to share outside information.
Can you cite your information source about such large-scale Geo Engineering that currently exists? So far I have only read about possible ideas.
A very interesting article, indeed. If San Francisco can reduce use by one third over the past thirty years, Vally farmers can also get busy with improving efficiency instead of constantly whining and sniveling. It has always appeared to me that the farming community as a whole claim ALL the water belongs to farmers.
This is utter nonsense. Famers have been improving water efficiency for years in a number of different ways. Farmers never claimed ALL the water belongs to them.
Nice to read some good news on the water supply. Even better news would be if San Francisco obtained its water from a desalinization plant, tore down the Hetch Hetchy Reservoir to make Yosemite National Park whole, and allowed all of our regional water to stay in our region.
When farmers use water that soaks into the ground, they replenish the water table. The amount of water that farmers waste may be overstated. Water loss due to transpiration cannot be avoided and should not be considered waste. Vegetation will always exist and transpire, whether on a farm or in a natural area.
Rather than focus on blaming, we would be well served to focus on doing better. Give San Francisco credit for its conservation efforts and continuously strive to make the city more reliant on its local water sources.
The trick with irrigation farming is that you have to track water *quality* as well as quantity! Water used for farming tends to degrade in quality as it picks up salts from the soil, so farm runoff can actually poison an aquifer as the freshwater slowly gains salt. This is a serious concern in the Tuolumne basin, where there are no significant surface outflows to the ocean, and already is permanently fallowing fields in the San Joaquin Valley as the basin concentrates salt and poisons the root zone in low-lying fields. This isn’t to deny your point that farm water is reusable, it just has a limit on reuse. City use actually has similar issues, where wastewater treatment can remove pathogens and solids but leaves salts present. That said, most water use in the state is agricultural and cities tend to empty treated wastewater into surface waters instead of groundwater aquifers, so the cities’ impacts are less cumulative. Water drainage is just as important a topic as irrigation!
I’d be curious to hear about how water banking could be applied in the ‘extraction’ part of the process. Would it be used to offset surface water usage, or actively added to surface waters as an artificial spring? The latter seems unlikely but could be novel if the energy requirements worked out favorably. Also curious on how groundwater banks would offset/augment surface reservoirs.
I like your questions, Garrett.
Questions such as yours, and more questions, must be answered before a group of decisions makers get side tracked by some good sounding benefits. There generally are more questions that do not get answered with any semblance of satisfaction, if at all. Many questions do NOT get asked.
If you get your answers or think of other questions please do return to inform valley citizens. Please.
I do think the Bay Area needs to be encouraged to discover other means of water supply. Great for them that they reduced their water use. Yet, is their reward that they get to share water from this county that has not even come to fruition?
Do you know who came up with this idea under the value of collaboration versus the cost of conflict. It sounds simple, but is it in the long run?
That is why wise questions and applied knowledge are superior to just thinking something sounds practical, ENOUGH, to venture in without all the answers. Water is NOT to be treated as if salt and runoff are not part of the equation.
Thank you for widening the scope.
very clear and good article easy to understand. Thank you