- Author: Daniel K Macon
As of this writing, we're on track for a "normal" rainfall year here in Auburn. Even if the rainy season ended with last week's storm, we'll finish the year at 90 percent of our long term annual average. In the high country to our east, the story is even better - the snow-water equivalent is sitting at 110% of the April 1 average. For the Nevada Irrigation District (NID), which serves western Nevada County and northwestern Placer County, low elevation rain and high elevation snowpack are a great combination - their reservoirs are full!
But despite all of this positive weather and water supply news, those of us who rely on NID water to irrigate pasture and other crops are facing the prospect of drought through the late spring and early summer (and possibly beyond). Earlier this year, a massive landslide damaged a portion of PG&E's South Yuba Canal below Spaulding Reservoir. In addition to moving water out of the high country for power generation, the canal allows NID to bring water from its upper watersheds down to Scotts Flat Reservoir east of Nevada City. From Scotts Flat, NID supplies farmers and ranchers throughout western Nevada County.
At the same time, PG&E's Spaulding 1 Power House also suffered significant damage, putting it offline. All of the water that NID moves down to Rollins Reservoir near Colfax comes through Spaulding 1 - and Rollins serves farmers and ranchers in North Auburn, Lincoln, and Sheridan.
At the moment, PG&E hopes to have a partial repair in place by early June, but NID will need to rely on it's low-elevation storage in Scotts Flat and Rollins to serve its irrigation customers. Without the ability to move water below Spaulding, NID projects that both Scotts Flat and Rollins will be significantly drawn down by mid-June. This week, PG&E indicated that some repairs might take much longer (stretching into August or September - more information here). Consequently, they are asking for voluntary conservation measures from both irrigation customers and treated water customers. As more information becomes available, I suspect that mandatory cutbacks may be on the table. The NID Board of Director will meet tomorrow to discuss the situation.
All of this brings ranchers to the unique position of managing for drought during an otherwise "normal" water year. Most of the recent droughts we've experienced in the foothills have been the result of a lack of precipitation and/or warm temperatures during the fall, winter, or spring months (see my post "A Taxonomy of Rangeland Drought" from February 2022). This year's "accidental" summer drought poses a different set of challenges. Many of us want to do our part to help NID conserve water during this emergency, but what are the options that best keep our pastures alive and our our livestock fed?
Traditionally, NID has conserved water during drought by asking customers to reduce the miner's inches they purchase - easy to accomplish simply by changing out the boards in our boxes. In thinking about my own sheep operation, reducing our 8 miner's inches to 6 would mean one of two options: first, I could simply try to put 66 gallons per minute out through a sprinkler system designed to deliver 88 gallons per minute, or second, I could leave one zone of the pasture unirrigated all season. At this point, option 2 makes more sense - I would optimize irrigation on the most productive portions of my pasture and let the least productive section go dry. In the long run, this means replanting that portion of the pasture (or permanently turning it back into less productive dryland forage).
An alternative that NID may not be equipped to accommodate would be to end my irrigation season earlier than normal - that is, to shut off the water to my pasture around September 1. The bulk of my pasture growth comes in the first 8 weeks of the irrigation season. When we hit the high temperatures and long days of July, forage growth goes into a "summer slump" and productivity declines. As the days grow shorter and the temperatures moderate (usually!) in September, our water demand falls and our pasture forages begin preparing for dormancy. With full water deliveries through the end of August, my pastures would likely survive if we didn't irrigate for the last 7 weeks of the season.
In either case, we'll need to think about balancing livestock demand with a diminished supply of summer forage. We can either reduce the number of mouths on the pasture, or purchase more feed (either hay or rented pasture) - or some combination of the two. One of our strategies has always been to match our production cycle with the forage cycle - we typically wean and sell our lambs as the spring flush of forage is ending (in essence, reducing our stocking rate to match a lower carrying capacity in the midst of the summer). Since we also rely on NID for our stock water, I'll need to think about strategies to ensure we're able to get water to the sheep through the summer, as well. NID will credit our accounts for this voluntary reduction in water, which could offset the cost of buying feed. In addition, a voluntary reduction this year will not impact our water deliveries in future years.
We've created a Drought Decision Support Tool to help you consider YOUR options. The first step is to inventory your forage resources for the coming summer and fall. Are you locked in, or do you have some flexibility in accessing additional leased pasture? Alternatively, are there some steps you can take to reduce your stocking rate this summer (like weaning your calves early or keeping fewer replacement heifers)? We've also developed a series of Excel spreadsheets to help you compare the financial impacts of culling females versus weaning early versus buying feed.
During the 2012-2016 drought, my mantra was "hope for the best, but prepare for the worst." While I certainly hope that PG&E is able to complete the repairs at Spaulding more quickly than they are currently projecting, I think it's time to prepare for the worst.
- Author: Daniel K Macon
Later this month, the USDA's National Animal Health Monitoring System (NAHMS) will kick off its fourth national study of the U.S. sheep industry. This project is entirely voluntary on the part of producers, and will provide the industry with critical information about high priority animal health and management issues. I hope you'll consider participating!
According to NAHMS, the study has five primary objectives:
- Describe the occurrence of common, economically important sheep diseases, as well as management and biosecurity practices associated with those diseases;
- Describe antimicrobial (antibiotic) stewardship on sheep operations and estimate the prevalence of enteric microbes and antimicrobial resistance patterns;
- Describe producer practices regarding internal parasite control and dewormer resistance;
- Describe changes in animal health, nutrition, and management practices in the U.S. sheep industry since 1996; and
- Provide serum to include in the serologic bank for future research.
In Phase I (January-February 2024) of the study, the National Agricultural Statistics Service will contact selected producers to complete a general sheep management questionnaire. These producers will also have an opportunity to participate in additional research activities.
During Phase II (April-July 2024), a subset of these producers will be contacted by USDA's Veterinary Services to complete a more detailed questionnaire and provide biological samples, including
- Fecal Parasite Test: Fecal egg counts on a composit sample will provide information about parasite burden. Select operations will also be examined for dewormer effectiveness.
- Enteric Microbe Test: Detection and antimicrobial susceptibility testing of Salmonella, E. coli, and Campylobacter in your sheep.
- Lameness Pathogens Test: Swabs will be tested for lameness pathogens on the operation.
If your operation is selected for these tests, you'll receive individualized reports for each category (these tests would cost more than $3,000 if you had to have your own veterinarian conduct them). The results will also be used to help build our understanding about key sheep health issues. From an extension perspective, these results will help me focus future workshops and materials around the issues that matter most to commercial producers! And again, your privacy will be protected - participation is entirely voluntary, and no data will be reported in any way that could reveal the identity of a participant.
I hope you'll participate! For more information, check out the NAHMS sheep study webpage!