More than another foot of snow is likely to be added to the upper reaches of the western Sierra this weekend.

That — coupled with other storms since the first of the month and those yet to come — is expected to steer California clear of drought conditions this year, according to the National Weather Service.

It is against that backdrop the South San Joaquin Irrigation District board meets today at 9 a.m. to set the start of the 2024 irrigation season.

And if the board concurs with the staff recommendation, that date will be March 20.

There is likely to be sufficient water this year to cover all of SSJID’s water deliveries to farms and the cities of Manteca, Tracy, as well as Lathrop with no restrictions.

That is because the relatively anemic 56 percent of snowpack average on Feb. 1 or the Stanislaus River watershed that supplies  SJJID and Oakdale Irrigation District with 600,000 acre feet of water split evenly is expected to benefit from a series of storms that have hit — and are expected to — the region this month.

The wetter February comes on the heels of a warmer than normal December and a drier than usual January.

A March 20 start date would  allow farmers time to complete new connections to the SSJID system as well as allow district crews time to address storm damage and other maintenance needs.

While what Mother Nature provides on the watershed every year is a big factor driving availability of water supplies, there are other factors at play as well that determine the board’s decision when to start the irrigation season.

Completing needed repairs and maintenance work during the winter while dodging storms is one concern.

The other is how the Bureau of Reclamation manages the OID and SSJID conservation account at Melones Reservoir.

The 1988 Agreement is what the two districts entered into with the Bureau in return for New Melones Reservoir inundating their Melones Dam site.

The agreement entitles both districts to the first 600,000 acre-feet (AF) of inflow into New Melones Reservoir.

When inflow is less than the 600,000 AF, the districts are entitled to the actual inflow plus one-third the difference between 600,000 minus the inflow.

The 2023 Water Year ended as one of the largest precipitation years on record with Stanislaus River unimpaired runoff at Goodwin Dam calculated at over 2.5 million acre-feet.

New Melones Reservoir started the 2024 Water Year essentially full.

The lack of precipitation in the fall and early winter placed the current San Joaquin River Hydrologic Index at “critical” in December and “dry” in January.

New Melones Reservoir is currently sitting at just over 1.981 million AF which is over its maximum storage volume during the flood control season.

Reclamation has increased releases from New Melones and Goodwin to 1,500 cubic feet per second (cfs) resulting in approximately 84,000 AF of spill.

This is significant in that OID and SSJID, per the 1988 agreement, jointly hold a conservation account in New Melones Reservoir which is vacated first in the event of flood control spills.

With additional storm activity forecasted, it is likely that the entire conservation account may be vacated sometime in 2024.

That said, the prospects of a strong finish to the wet season — which will be verified one way or the other on March 1  — would provide ample water from inflow to meet all district needs this year even if the conservation account was depleted.

The wet weather pattern returning to Manteca-Ripon-Lathrop late Wednesday and Thursday is expected to provide between 0.10 and 0.25 inches of rain.

The Sierra crest is expected to see 6 inches of snow.

A second storm hitting Friday will bring high winds, between 12 and 18 inches of snow at the higher elevations and possibly up to an inch of rain in the valley before tapering off by Tuesday.

To contact Dennis Wyatt, email dwyatt@mantecabulletin.com