NORTH HOLLYWOOD >> A series of storms this week washed out homeless camps from the Sepulveda Basin to east Los Angeles, leaving residents scrambling for safer refuge.

Tonight, L.A. Mayor Eric Garcetti helped launch a mammoth effort to find them during the largest homeless count in the nation.

The 2017 Greater Los Angeles Homeless Count kicked off in the San Fernando and San Gabriel valleys, as well as east Los Angeles, to begin a three-day tally during the chill of winter by an expected 8,000 community volunteers, a record.

Garcetti joined county officials at Los Angeles Family Housing Corp., where he launched the tally through the streets and alleys of North Hollywood. The valleywide count will be aided by nearly 1,150 volunteers.

“Having a home is a right that belongs to everyone,” Garcetti said in a statement. “We need an accurate tally, but the homeless count isn’t about statistics — it’s about lifting up men, women, and children who are the face of a human crisis.

“Their stories demand our attention, and their circumstances compel us to action.”

• RELATED STORY: LA County takes on largest homeless count in US – with a lot of help

The annual count, considered the largest in the nation, helps paint a picture of homelessness across Los Angeles to help obtain federal funds and deliver services where needed. It also follows recent scrutiny on how to solve what Los Angeles officials have dubbed a “homelessness crisis.”

The count will continue Wednesday in West L.A. and the South Bay, and end Thursday in the Antelope Valley, downtown and South Los Angeles.

The goal set by the Los Angeles Homeless Services Authority is to locate people who are homeless within every census tract in Los Angeles County.

This year’s homeless count cost $1.1 million, half paid by the city, half by the county.

Last year’s count, which cost $1.3 million, revealed that on any night the county has around 47,000 homeless people, up 5.7 percent from 2015, and up 11 within the city of Los Angeles, according to the Los Angeles Housing Services Authority.

In the San Fernando Valley, the homeless population grew to 7,335, an increase of 35 percent.

At the same time, veteran homelessness fell 30 percent across Los Angeles County, according to the federally mandated tally, and the number of homeless families fell by 18 percent in 2016 from the year before. The number of homeless women, however, increased.

• PHOTO ESSAY: Housing the Homeless

A report released in October by the Downtown Women’s Action Coalition found that since 2013, there has been a 55 percent increase in the number of women experiencing homelessness in Los Angeles County.

A survey of 371 homeless or formerly homeless women found that 60 percent were 51 years old and older — a nearly 8 percent increase from 2013.

Leaders from the city and county of Los Angeles declared homelessness an emergency in 2015 and have since allocated millions to bolster rapid rehousing efforts and other services. But affordable housing remains a challenge.

In November, Los Angeles voters passed Proposition HHH, the city’s property tax bond measure, which is expected to raise about $1.2 billion to build supportive housing for the homeless. In March, county voters will decide on a quarter-cent sales tax to pay for social services linked to those new permanent supportive housing units.

“The city is in the midst of a crisis, and the Greater Los Angeles Homeless Count will help provide current data to help us target where supportive services are needed the most,” said Los Angeles City Councilmember Mitch O’Farrell, whose district spans from Hollywood to Atwater Village. “Only then can we determine exactly where those resources should be directed in my district and beyond.”

• RELATED STORY: How a once-seedy North Hollywood motel has become a model for helping the homeless

Tonight in North Hollywood, Garcetti was joined by county Supervisor Mark Ridley-Thomas, Los Angeles Controller Ron Galperin, LAHSA Director Peter Lynn and LAHSA Commission Chair Wendy Greuel.

Also in attendance was Stephanie Klasky-Gamer, president & CEO of L.A. Family Housing, a nonprofit agency and shelter that is now constructing a $40-million hub for permanent supportive housing, health care, integrated services and homeless outreach for the entire Valley.

In the past week, a series of storms flooded homeless encampments from the Sepulveda Basin in Lake Balboa to Wilmington, forcing rescues by Los Angeles firefighters

In the past year, violent crime rose across Los Angeles, including spikes in homicides, robberies and property crimes across the San Fernando Valley that police blamed on the rise in homeless, many who they say commit crimes in order to feed drug habits.

Last year’s homeless tally took place before the county and city adopted a series of homeless initiatives. Officials hope to view this year’s count as one way to track their progress.

“I want to emphasize just how important these numbers are,” said county Supervisor Sheila Kuehl, who represents much of the Valley. “Last year, the number of men and women in the Valley who were experiencing homelessness increased by 35 percent.

“Even in the very early days of this effort, and in the face of growing economic circumstances pushing more individuals out of their housing,” she said, “we hope to find that homelessness does, indeed, respond to resources and I am grateful to all the Valley residents who are participating in this massive three-day effort.”