On July 15, 2013, Cynda Collins Arsenault was standing in her house, worrying.

Her boldly named garden party—the Women’s Work, Wisdom and Wine Festival—was on the very near horizon. In just a few hours, her yard would be teeming with visitors, but unfortunately, dark clouds had arrived first. The sky above her Superior, Colorado home had opened wide for an early-afternoon storm, and it looked as though the rain was about to wreck the whole event. The only thing she could do was watch and wait.

At around 2 p.m., with just an hour to spare, Collins Arsenault breathed a sigh of relief: at last, the storm clouds had dissipated.

Within the hour, her party was in full swing. Neighborhood boys circulated through the crowd, holding paper plates of the usual, bite-sized party fare. Representatives from 60 Denver- and Boulder-based nonprofits—all of them run by women, or boasting missions that support women—had arrived, tables in tow, and had set up shop in her backyard to share stories and talk about their work. This was a party with a purpose. Collins Arsenault, long an active philanthropist in Colorado, had realized there was a need for networking and cross-genre conversation among nonprofits benefitting women and children; she was more than happy to lend her yard to the cause.

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Immediately, Collins Arsenault says, she could tell she had hit a nerve in the community. “It was so high-energy. People kept saying, ‘Oh, well, next year,’ and I kept saying, ‘No, no, this is just a one-time event!’” Collins Arsenault recalls, laughing. “And then I started getting the emails.”

Collins Arsenault’s inbox began to overflow. Emails arrived from women who had made connections at the event, telling her about new collaborations that had grown out of their backyard conversations. Some women, previously unconnected to philanthropy in Colorado, wrote to her about new involvement. Others still—women who had missed the event—emailed in the hopes of putting their names down “for the next one.”

With a simple garden party, Collins Arsenault had started something. Seeing no other option, she organized another Women’s Work, Wisdom and Wine Festival the following July at Denver’s RedLine Gallery. In its second year, the event attracted 87 organizations and around 500 attendees. “At that point, it was clear that it was beyond my capabilities,” she says.

But the seed had taken root, and a group of women—all of whom lead other nonprofit organizations by day—volunteered to help with, again, “the next one.”

With the help of these 13 women, who now make up the steering committee for the event, the Women’s Work, Wisdom and Wine Festival partnered with the Women’s Foundation of Colorado and underwent a rebranding. In its third year, the little garden party that started in Superior—now known as the Women Powering Change conference—has grown into an event that will welcome 100 Colorado-based women’s nonprofits and around 1,000 attendees when it takes the Exdo Event Center on July 9.

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As in previous years, organizers of the conference were happily surprised with the volume of interest. In less than a month, all 100 spots had been filled by Colorado nonprofits, with many others spilling onto a waitlist.

Lauren Casteel, president and CEO of the Women’s Foundation of Colorado says she’s not shocked that Colorado women—and men—care about issues affecting women and girls around the world. “Colorado has a really robust nonprofit environment. It’s one that has been supported with great passion by other sectors as well,” Casteel says. And that interest spans socio-economic boundaries as well. “Oftentimes it’s not known that people in lower income brackets might give proportionately more of their income. Through all levels of our community, there’s huge participation.”

According to Anne Elgerd, founder and director of Colorado-based social enterprise Beautiful World (and a member of the conference’s steering committee), the event is a win-win-win. Nonprofits have a chance to learn from one another, people who want to volunteer time or money to organizations can find causes they support, and smaller nonprofits can find passionate donors.

“It’s really about bringing people together and harnessing the power of collaboration to catalyze social change,” Elgerd says.

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Ultimately, it’s also about bringing out the philanthropist in each person, which Casteel says isn’t that hard in Colorado. During a recent visit to Harrison High School in Colorado Springs—where a majority of students receive free or reduced lunches—Casteel met a group of girls who had collected blankets to donate to Urban Peak youth shelter. When she asked the girls if they knew what a philanthropist was, they cried out: Oprah!

“And I said, ‘No, you are.’ Philanthropy is about caring about human kind. That’s the essence of it,” Casteel says. “I could tell you stories of people I meet all across the state who are giving from a love of human kind. Gathering the power of that philanthropy and of women’s philanthropy is critical. People say women hold up half the sky. And if that’s the case, don’t we want that half of the sky to shine just as brightly?”

Attend: The Women Powering Change conference takes place Thursday, July 9, 4 to 7 p.m.; Exdo Event Center, 1399 35th St. Individuals can register online for free.

Near and far: Of the 100 Colorado-based organizations that will be present at this Thursday’s Women Powering Change Conference, 46 have a mission with local scope, while 52 turn their eyes to the rest of the world. Check out the full list.

(Read 5280‘s special report on the Colorado Woman)