The Agua Fund is a private foundation that appears to be a philanthropic vehicle for Catherine Mellon Conover, a left-of-center environmentalist donor and activist who is an heiress to the Mellon fortune and is a listed director of the foundation on its nonprofit tax returns. ^{1 2  3  4} It focuses primarily on environmentalist causes, with a geographic emphasis on the mid-Atlantic states. ⁴

Background

The Agua Fund refers to itself simply as a private foundation and does not publicize the source of its more than $8 million in assets. ⁵ Inside Philanthropy notes, “This funder maintains a low profile, and little is publicly known about its financial origins or the individuals behind it.” ⁴

Based on public records, media reports, and other publicly available evidence it appears to be the private foundation of Catherine Mellon Conover, an heiress to the fortune of industrialist and longtime Treasury Secretary Andrew W. Mellon.  ^{1  6  2  3}

Conover the daughter of his Andrew Mellon’s son Paul Mellon, who co-founded the Andrew W. Mellon Foundation in 1940. ⁷ She was born Catherine Conover Mellon and became Catherine Warner upon her marriage to then-U.S. Attorney and later U.S. Senator John Warner (R-VA).  ^{6  8} After her 1973 divorce from Warner, she legally changed her name again, transposing her father’s and mother’s names to become Catherine Mellon Conover. ^{6  8}

She is almost certainly the “Catherine M. Conover” of Washington, D.C. who created the Agua Fund in 2002 with an $8 million donation and who continues to fund it to this day. ^{1  2  3} Conover was the Agua Fund’s founding board president, and is the only person to have remained on the foundation’s board throughout its entire existence.  ¹

Among other connections, Catherine Mellon Conover is a co-founder of prominent left-of-center environmental publisher Island Press.  ⁹ The Agua Fund and her family’s Andrew W. Mellon Foundation, along with the Ford Foundation and Joyce Foundation, were the publisher’s original seed funders. ⁹

Leadership

As of 2026, the executive director of Agua Fund was Ann Mills, who was Deputy Undersecretary for Natural Resources and the Environment in the Obama administration’s Department of Agriculture, a chief of staff to former U.S. Senator Tom Daschle (D-SD) and former California Lieutenant Governor Leo McCarthy (D), and a legislative staffer for U.S. Senator Richard Durbin (D-IL). ¹⁰ Mills had also previously worked at the left-of-center environmental group American Rivers.  ¹⁰

In 2024, Agua Fund tax returns reported that Mills received $216,835 in compensation. ¹

Financials

Conover launched the Agua Fund in 2002 with an $8 million donation and regularly makes additional donations to it. ¹ She is responsible for the majority, if not the entirety, of the $53,414,908 donated to the group since its creation in 2002, according to tax records.  ¹

Grantmaking

The Agua Fund publishes an annual breakdown of its grants by interest area. ¹¹ Its largest giving area is in environmental stewardship and activism, with grants to local, national, and international organizations regularly accounting for half or more of its total annual outlay.  ¹¹ Its other focus areas are arts, culture, and education; civic engagement; and social services.  ¹¹

In 2024, it reported making $3,070,000 in grants.  ¹ The largest grants were $150,000 to the Alliance for the Shenandoah Valley, $150,000 to the Piedmont Environmental Council, $115,000 to the National Wildlife Federation, $106,000 to the Potomac Riverkeeper Network, and $100,000 to the Southern Environmental Law Center.  ¹

Other notable 2024 grants include $40,000 to the Lawyers’ Committee for Civil Rights Under Law, $40,000 to Make the Road Pennsylvania, $75,000 to New Virginia Majority, $80,000 to PolicyLink, $80,000 to the Tides Foundation’s Movement Voter Fund, and $60,000 to Virginia Organizing.  ¹

1. “Agua Fund Inc.” ProPublica Nonprofit Explorer. Accessed January 8, 2026. https://projects.propublica.org/nonprofits/organizations/113659697.
2. “Wealth List.” Washington Life Magazine, June 2007. https://www.washingtonlife.com/issues/june-2007/WEALTH/page68.php.
3. Mewbor, Mary K. “Real Estate News.” Washington Life Magazine, May 2005. https://washingtonlife.com/issues/2005-05/realestate/.
4. “Agua Fund.” Inside Philanthropy, December 13, 2024. https://www.insidephilanthropy.com/find-a-grant/grants-a/aguafund.
5. “Agua Fund.” Aguafund. Accessed January 8, 2026. https://www.aguafund.org/.
6. “Catherine Conover.” LittleSis. Accessed January 8, 2026. https://littlesis.org/person/98366-Catherine_Conover/data.
7. “History and Founders of the Mellon Foundation.” Mellon Foundation. Accessed January 8, 2026. https://www.mellon.org/history.
8. Hulse, Carl. “John Warner, Genteel Senator from Virginia, Dies at 94.” The New York Times, May 26, 2021. https://www.nytimes.com/2021/05/26/us/politics/john-warner-genteel-senator-from-virginia-dies-at-94.html.
9. “Leadership Transition.” Island Press, April 30, 2016. https://islandpress.org/leadership-transition.
10. “Staff.” Aguafund. Accessed January 8, 2026. https://www.aguafund.org/staff/.
11. “Grants.” Aguafund. Accessed January 8, 2026. https://www.aguafund.org/grants/.