What started as a simple picture of a whale’s tail emblazoned on a specialized California license plate decades ago has morphed into one of the most successful environmental programs in the state.

The Whale Tail license plate — celebrating its 20th anniversary — continues to be popular among motorists. Since 1997, 243,000 plates were sold and the program has raised $95 million, according to the California Coastal Commission, the state agency that doles out cash from the Environmental License Plate (ELP) fund.

As expected, on a per capita basis, sales are highest among coast dwellers. Yet the whale plates are surprisingly popular among inland motorists in Southern California, said Chris Parry, the commission’s public education manager.

ZIP code data shows motorists from the San Gabriel Valley, San Bernardino and Riverside counties are among the top purchasers of the specialized license plates in the state, Parry said.

The money is used for the cleanup of beaches, rivers, creeks as well as anti-pollution education programs aimed at school-aged children, she said.

“For instance, the San Gabriel Valley is actually a pretty good market for us,” she said. “There is a strong connection to the coast from the people of the San Gabriel Valley because they travel to the coast; it is a popular thing to do, especially in the summer.”

In 2009, the latest year of geographic data available, Los Angeles County led with 26,577 plates on the road. Orange County was second, with 16,770, followed by San Diego County, 14,135 and Ventura County, 4,593. In the Inland Empire, there were 6,028 licenses in Riverside County, and 4,362 in San Bernardino County.

Many inlanders visit Los Angeles and Orange county beaches, she said. They want to ensure the ocean waters are clean, too.

Another reason for the high numbers of inland motorists is the expansion of the annual California Coastal Cleanup Day held last weekend.

At one time, the day was only for picking up trash on the beach — now it includes cleanup of the Los Angeles, San Gabriel and Santa Ana rivers, tributaries that empty into the ocean and often carry pollutants.

“It’s for the whole inland watershed, not just the coast,” Parry explained.

Heal The Bay runs both the yearly cleanup that’s now in its 32nd year, as well as a monthly program called “Nothing But Sand” that has grown from 100 people to 700 people per month.

The program will celebrate the 20th anniversary Oct. 21 at Playa del Rey at the Ballona Creek wetlands. None of this would exist without the Whale Tail funding, said Meredith McCarthy, director of programs.

“That kind of dedicated funding that allows that growth is rare in the nonprofit world. It keeps on going,” she said.

Nicole Muldoon, 53, is a Pasadena resident who has kept her Whale Tail license plate for eight years, despite two vanity plate changes. The Whale Tail plate costs $50; a Whale Tail vanity plate costs $103.

“I’m willing to pay the extra cash to know it will go to keeping our coastal waters clean and protecting the whales and the wildlife in the ocean,” Muldoon said on Thursday, before she entered the Whole Foods store on Arroyo Parkway.

Long Beach has also benefited from ELP dollars.

“The nonprofit Aquarium of the Pacific is pleased to be one of the recipients of a California Coastal Commission grant for climate change resiliency outreach,” said Dr. Jerry Schubel, the aquarium’s president.

The aquarium received nearly a $12,000 grant for pilot testing demonstrations, hands-on activities and fostering conversations about building climate resiliency.

Other examples of ELP funded programs include:

• $33,272 to University of Redlands to create a mobile app that plots the location of whales and other marine mammals spotted by app users

• Field trips for Native American students at Sherman High School in Riverside to Malibu, Point Dume and the Palos Verdes Peninsula for marine life study, said Parry. “There are great benefits of the experience of actually going to the coast and learning about the ocean.”

• $19,900 to the Newport Bay Conservancy for underserved community students to visit Upper Newport Bay and participate in canoe rides and hands-on activities.

• $5,640 to the El Monte Union High School District for 140 Arroyo High school students to learn about watershed environments in the Los Angeles River.

• $9,950 for students at George Porter Middle School in Granada Hills to study seashore habitats.

The program ran into a speed bump in 2008 when famous artist Wyland asked the state to stop using his image of a misty whale fluke. He had requested 20 percent of the revenue go to his nonprofit foundation. The Coastal Commission retired the image and held a contest for a new artist.

Laguna Beach digital artist Bill Atkins won and his design — a much more colorful humpback whale’s fluke positioned against a blue sky and puffy clouds — was accepted in 2011 and remains the image on the license plate today.

Atkins, who has a studio in Laguna and a booth at the Sawdust Festival this summer, says it’s the most famous image he’s ever created. He wasn’t aware how successful the Whale Tale license plate program had become.

“Really? Well, that’s terrific. I couldn’t be happier,” he said during an interview Thursday. “I’m all about creating art that makes a difference.”