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Arizona Hydrological Society

  • Tucson, AZ
  • Tax-exempt since Oct. 1987
  • EIN: 74-2458455

Organization summary

Type of Nonprofit

Designated as a Business leagues, chambers of commerce, real estate boards, etc, created for the improvement of business conditions.

Donations to this organization are not tax deductible.

Summary charts: organization finances over time

Revenue
$100k (2023)

Expenses
$40.2k (2023)

Total Assets
$280k (2023)

Total Liabilities
$0 (2023)

Source: Form 990 tax filings from 2011 to 2023

Tax Filings by Year

Form 990 is an information return that most organizations claiming federal tax-exempt status must file yearly with the IRS. Nonprofit Explorer has IRS digitized Form 990 data for filings processed in 2012 and later. If this organization filed an amended return, it may not be reflected below. Duplicate download links may indicate a resubmission or amendment to this organization's original return. Form 990 data is from the IRS.

Fiscal Year Ending Dec.
2023

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$100,299
Expenses
$40,194
Net Income
$60,105
Net Assets
$280,188
Notable Sources of Revenue Percent of Total Revenue
Contributions $1,800
1.8%
Program Services $15,720
15.7%
Investment Income $5,071
5.1%
Net Fundraising $62,060
61.9%
Sales of Assets $0
Net Inventory Sales $0
Other Revenue $1,933
1.9%
Assets/Debt
Total Assets $280,188
Total Liabilities $0
Net Assets $280,188
Compensation
Key Employees and Officers Compensation Other
Nathan Miller (President) $0 $0
Christopher Brooks (Vice President) $0 $0
John Villinski (Treasurer) $0 $0

Document Links

990-EZ
Filed on March 26, 2024

Short form tax return for a nonprofit’s activities, finances, and governance

View Filing
XML

Fiscal Year Ending Dec.
2022

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$73,839
Expenses
$49,737
Net Income
$24,102
Net Assets
$209,627
Notable Sources of Revenue Percent of Total Revenue
Contributions $776
1.1%
Program Services $11,330
15.3%
Investment Income $4,424
6.0%
Net Fundraising $35,237
47.7%
Sales of Assets $0
Net Inventory Sales $1,499
2.0%
Other Revenue $3,144
4.3%
Assets/Debt
Total Assets $209,627
Total Liabilities $0
Net Assets $209,627
Compensation
Key Employees and Officers Compensation Other
Michael Block (President) $0 $0
Christopher Brooks (Vice President) $0 $0
Marla Odom (Secretary) $0 $0
John Villinski (Treasurer) $0 $0
Elizabeth Profitt (Director) $0 $0
+ View more people

Document Links

990-EZ
Filed on May 17, 2023

Short form tax return for a nonprofit’s activities, finances, and governance

View Filing
XML

Fiscal Year Ending Dec.
2021

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$38,961
Expenses
$24,010
Net Income
$14,951
Net Assets
$200,699
Notable Sources of Revenue Percent of Total Revenue
Contributions $1,500
3.9%
Program Services $0
Investment Income $5,539
14.2%
Net Fundraising $21,782
55.9%
Sales of Assets $0
Net Inventory Sales $0
Other Revenue $0
Assets/Debt
Total Assets $200,699
Total Liabilities $0
Net Assets $200,699
Compensation
Key Employees and Officers Compensation Other
John Villinski (Treasurer) $0 $0
Mike Hulst (President) $0 $0
David Sampson (Director) $0 $0
Robert Balcells (Director) $0 $0
Marla Odom (Secretary) $0 $0
Christopher Brooks (Director) $0 $0
Erin Young (Director) $0 $0
Elizabeth Proffitt (Director) $0 $0
Michael Block (Vice President) $0 $0
+ View more people

Document Links

990-EZ
Filed on Aug. 1, 2022

Short form tax return for a nonprofit’s activities, finances, and governance

View Filing
XML

Fiscal Year Ending Dec.
2020

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$72,680
Expenses
$67,465
Net Income
$5,215
Net Assets
$171,096
Notable Sources of Revenue Percent of Total Revenue
Contributions $1,500
2.1%
Program Services $0
Investment Income $3,100
4.3%
Net Fundraising $57,220
78.7%
Sales of Assets $0
Net Inventory Sales $0
Other Revenue $0
Assets/Debt
Total Assets $171,096
Total Liabilities $0
Net Assets $171,096
Compensation
Key Employees and Officers Compensation Other
John Villinski (Treasurer) $0 $0
Mike Hulst (President) $0 $0
David Sampson (Director) $0 $0
Robert Balcells (Director) $0 $0
Marla Odom (Secretary) $0 $0
Christopher Brooks (Director) $0 $0
Erin Young (Director) $0 $0
Elizabeth Proffitt (Director) $0 $0
Michael Block (Vice President) $0 $0
+ View more people

Document Links

990-EZ
Filed on May 10, 2021

Short form tax return for a nonprofit’s activities, finances, and governance

View Filing
PDF XML

Fiscal Year Ending Dec.
2019

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$73,862
Expenses
$34,266
Net Income
$39,596
Net Assets
$162,463
Notable Sources of Revenue Percent of Total Revenue
Contributions $1,200
1.6%
Program Services $0
Investment Income $3,343
4.5%
Net Fundraising $60,679
82.2%
Sales of Assets $0
Net Inventory Sales $0
Other Revenue $0
Assets/Debt
Total Assets $162,463
Total Liabilities $0
Net Assets $162,463
Compensation
Key Employees and Officers Compensation Other
John Villinski (Treasurer) $0 $0
Mike Hulst (President) $0 $0
Robert Balcells (Director) $0 $0
Marla Odom (Secretary) $0 $0
Stephen P Flora (Director) $0 $0
David Sampson (Director) $0 $0
Sharon Masek Lopez (Director) $0 $0
Michael Block (Vice President) $0 $0
Lee Anna Walker (Director) $0 $0
+ View more people

Document Links

990-EZ
Filed on Aug. 14, 2020

Short form tax return for a nonprofit’s activities, finances, and governance

View Filing
PDF XML

Fiscal Year Ending Dec.
2018

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$46,380
Expenses
$35,755
Net Income
$10,625
Net Assets
$114,756
Notable Sources of Revenue Percent of Total Revenue
Contributions $500
1.1%
Program Services $0
Investment Income $3,477
7.5%
Net Fundraising $35,663
76.9%
Sales of Assets $0
Net Inventory Sales $0
Other Revenue $0
Assets/Debt
Total Assets $114,756
Total Liabilities $0
Net Assets $114,756
Compensation
Key Employees and Officers Compensation Other
John Villinski (Treasurer) $0 $0
Mike Hulst (President) $0 $0
Robert Balcells (Director) $0 $0
Marla Odom (Secretary) $0 $0
Stephen P Flora (Director) $0 $0
Steve Sutherland (Director) $0 $0
Sharon Masek Lopez (Director) $0 $0
Mike Block (Vice President) $0 $0
Lee Anna Walker (Director) $0 $0
+ View more people

Document Links

990-EZ
Filed on June 27, 2019

Short form tax return for a nonprofit’s activities, finances, and governance

View Filing
PDF XML

Fiscal Year Ending Dec.
2017

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$49,404
Expenses
$50,625
Net Income
-$1,221
Net Assets
$109,190
Notable Sources of Revenue Percent of Total Revenue
Contributions $92
0.2%
Program Services $0
Investment Income $3,272
6.6%
Net Fundraising $34,970
70.8%
Sales of Assets $0
Net Inventory Sales $0
Other Revenue $0
Assets/Debt
Total Assets $109,190
Total Liabilities $0
Net Assets $109,190
Compensation
Key Employees and Officers Compensation Other
John Villinski (Treasurer) $0 $0
Mike Hulst (President) $0 $0
Steve Sutherland (Director) $0 $0
Marla Odom (Secretary) $0 $0
Margot Truini (Director) $0 $0
David Christiana (Vice President) $0 $0
Donald Bills (Director) $0 $0
Mike Block (Director) $0 $0
Lee Anna Walker (Director) $0 $0
+ View more people

Document Links

990-EZ
Filed on Aug. 21, 2018

Short form tax return for a nonprofit’s activities, finances, and governance

View Filing
XML

Fiscal Year Ending Dec.
2016

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$55,978
Expenses
$41,199
Net Income
$14,779
Net Assets
$112,738
Notable Sources of Revenue Percent of Total Revenue
Contributions $350
0.6%
Program Services $0
Investment Income $2,374
4.2%
Net Fundraising $38,678
69.1%
Sales of Assets $4,854
8.7%
Net Inventory Sales $0
Other Revenue $0
Assets/Debt
Total Assets $112,738
Total Liabilities $0
Net Assets $112,738
Compensation
Key Employees and Officers Compensation Other
John Villinski (Treasurer) $0 $0
Mike Hulst (President) $0 $0
Dennis Hall (Director) $0 $0
Marla Odom (Secretary) $0 $0
Mike Tomlinson (Director) $0 $0
David Christiana (Vice President) $0 $0
Donald Bills (Director) $0 $0
Mike Block (Director) $0 $0
Lee Anna Walker (Director) $0 $0
+ View more people

Document Links

990-EZ
Filed on July 31, 2017

Short form tax return for a nonprofit’s activities, finances, and governance

View Filing
PDF XML

Fiscal Year Ending Dec.
2015

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$33,489
Expenses
$36,391
Net Income
-$2,902
Net Assets
$93,396
Notable Sources of Revenue Percent of Total Revenue
Contributions $1,870
5.6%
Program Services $0
Investment Income $3,855
11.5%
Net Fundraising $21,257
63.5%
Sales of Assets $0
Net Inventory Sales $0
Other Revenue $0
Assets/Debt
Total Assets $93,396
Total Liabilities $0
Net Assets $93,396
Compensation
Key Employees and Officers Compensation Other
John Villinski (Treasurer) $0 $0
Mike Hulst (President) $0 $0
Dennis Hall (Director) $0 $0
Marla Odom (Secretary) $0 $0
Mike Tomlinson (Director) $0 $0
David Christiana (Vice President) $0 $0
Donal Bills (Director) $0 $0
Mike Block (Director) $0 $0
Lee Anna Walker (Director) $0 $0
+ View more people

Document Links

990-EZ
Filed on Aug. 3, 2016

Short form tax return for a nonprofit’s activities, finances, and governance

View Filing
PDF XML

Fiscal Year Ending Dec.
2014

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$33,368
Expenses
$43,460
Net Income
-$10,092
Net Assets
$99,134
Notable Sources of Revenue Percent of Total Revenue
Contributions $2,150
6.4%
Program Services $0
Investment Income $3,719
11.1%
Net Fundraising $22,752
68.2%
Sales of Assets $62
0.2%
Net Inventory Sales $0
Other Revenue $0
Assets/Debt
Total Assets $99,134
Total Liabilities $0
Net Assets $99,134
Compensation
Key Employees and Officers Compensation Other
John Villinski (Director) $0 $0
Mike Hulst (President) $0 $0
David Sampson (Director) $0 $0
Elizabeth Proffitt (Treasurer) $0 $0
Dennis Hall (Director) $0 $0
Marla Odom (Secretary) $0 $0
Damian L Gosch (Director) $0 $0
Mike Tomlinson (Director) $0 $0
Charlie Ester (Vice President) $0 $0
+ View more people

Document Links

990-EZ
Filed on May 14, 2015

Short form tax return for a nonprofit’s activities, finances, and governance

View Filing
PDF XML

Fiscal Year Ending Dec.
2013

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$47,900
Expenses
$41,466
Net Income
$6,434
Net Assets
$107,824
Notable Sources of Revenue Percent of Total Revenue
Contributions $550
1.1%
Program Services $0
Investment Income $1,530
3.2%
Net Fundraising $30,941
64.6%
Sales of Assets $58
0.1%
Net Inventory Sales $0
Other Revenue $0
Assets/Debt
Total Assets $107,824
Total Liabilities $0
Net Assets $107,824
Compensation
Key Employees and Officers Compensation Other
John Villinski (Director) $0 $0
Mike Hulst (President) $0 $0
Summer Waters (Director) $0 $0
Elizabeth Proffitt (Treasurer) $0 $0
Damien Gosch (Director) $0 $0
Marla Odom (Secretary) $0 $0
Damian L Gosch (Director) $0 $0
Mike Tomlinson (Director) $0 $0
Charlie Ester (Vice President) $0 $0
+ View more people

Document Links

990-EZ
Filed on May 14, 2014

Short form tax return for a nonprofit’s activities, finances, and governance

View Filing
PDF XML

Fiscal Year Ending Dec.
2012

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$47,231
Expenses
$37,345
Net Income
$9,886
Net Assets
$87,623
Notable Sources of Revenue Percent of Total Revenue
Contributions $2,269
4.8%
Program Services $0
Investment Income $891
1.9%
Net Fundraising $34,819
73.7%
Sales of Assets $0
Net Inventory Sales $0
Other Revenue $0
Assets/Debt
Total Assets $87,623
Total Liabilities $0
Net Assets $87,623

Document Links

990-EZ

Short form tax return for a nonprofit’s activities, finances, and governance

PDF
PDF (2 of 2)

Fiscal Year Ending Dec.
2011

Extracted Financial Data

Extracted Financial Data from 990-EZ
Revenue
$36,211
Expenses
$38,180
Net Income
-$1,969
Net Assets
$74,834
Notable Sources of Revenue Percent of Total Revenue
Contributions $0
Program Services $0
Investment Income $924
2.6%
Net Fundraising $28,607
79.0%
Sales of Assets $50
0.1%
Net Inventory Sales $0
Other Revenue $0
Assets/Debt
Total Assets $74,834
Total Liabilities $0
Net Assets $74,834

Document Links

990-EZ

Short form tax return for a nonprofit’s activities, finances, and governance

PDF

Fiscal Year Ending Dec.
2010

No Extracted Financial Data

Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.

Document Links

990-EZ

Short form tax return for a nonprofit’s activities, finances, and governance

PDF

Fiscal Year Ending Dec.
2009

No Extracted Financial Data

Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.

Document Links

990-EZ

Short form tax return for a nonprofit’s activities, finances, and governance

PDF

Fiscal Year Ending Dec.
2008

No Extracted Financial Data

Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.

Document Links

990-EZ

Short form tax return for a nonprofit’s activities, finances, and governance

PDF

Fiscal Year Ending Dec.
2007

No Extracted Financial Data

Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.

Document Links

990

Primary tax return for a nonprofit’s activities, finances, and governance

PDF

Fiscal Year Ending Dec.
2006

No Extracted Financial Data

Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.

Document Links

990

Primary tax return for a nonprofit’s activities, finances, and governance

PDF

Fiscal Year Ending Dec.
2005

No Extracted Financial Data

Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.

Document Links

990

Primary tax return for a nonprofit’s activities, finances, and governance

PDF

Fiscal Year Ending Dec.
2004

No Extracted Financial Data

Extracted financial data is not available for the forms filed in this tax period, but Form 990 documents are available for download.

Document Links

990

Primary tax return for a nonprofit’s activities, finances, and governance

PDF

About This Data

Nonprofit Explorer includes summary data for nonprofit tax returns and full Form 990 documents, in both PDF and digital formats.

The summary data contains information processed by the IRS during the 2012-2019 calendar years; this generally consists of filings for the 2011-2018 fiscal years, but may include older records. This data release includes only a subset of what can be found in the full Form 990s.

In addition to the raw summary data, we link to PDFs and digital copies of full Form 990 documents wherever possible. This consists of separate releases by the IRS of Form 990 documents processed by the agency, which we update regularly.

We also link to copies of audits nonprofit organizations that spent $750,000 or more in Federal grant money in a single fiscal year since 2016. These audits are copied from the Federal Audit Clearinghouse.

Which Organizations Are Here?

Every organization that has been recognized as tax exempt by the IRS has to file Form 990 every year, unless they make less than $200,000 in revenue and have less than $500,000 in assets, in which case they have to file form 990-EZ. Organizations making less than $50,000 don’t have to file either form but do have to let the IRS they’re still in business via a Form 990N "e-Postcard."

Nonprofit Explorer has organizations claiming tax exemption in each of the 27 subsections of the 501(c) section of the tax code, and which have filed a Form 990, Form 990EZ or Form 990PF. Taxable trusts and private foundations that are required to file a form 990PF are also included. Small organizations filing a Form 990N "e-Postcard" are not included in this data.

Types of Nonprofits

There are 27 nonprofit designations based on the numbered subsections of section 501(c) of the tax code. See the list »

Get the Data

For those interested in acquiring the original data from the source, here’s where our data comes from:

  • Raw filing data. Includes EINs and summary financials as structured data.
  • Exempt Organization profiles. Includes organization names, addresses, etc. You can merge this with the raw filing data using EIN numbers.
  • Form 990 documents. Prior to 2017, these documents were obtained and processed by Public.Resource.org and ProPublica. Bulk PDF downloads since 2017 are available from the IRS.
  • Form 990 documents as XML files. Includes complete filing data (financial details, names of officers, tax schedules, etc.) in machine-readable format. Only available for electronically filed documents. Electronic data released prior to October 2021 is also available through Amazon Web Services.
  • Audits. PDFs of single or program-specific audits for nonprofit organizations that spent $750,000 or more in Federal grant money in a single fiscal year. Available for fiscal year 2015 and later.

API

The data powering this website is available programmatically, via an API. Read the API documentation »

Byline

By Andrea Suozzo, Alec Glassford and Ash Ngu, ProPublica, and Brandon Roberts, Special to ProPublica.
Design by Jeff Frankl. Additional development by Ken Schwencke, Mike Tigas, and Sisi Wei.

E-file viewer adapted from IRS e-File Viewer by Ben Getson. Code for scraping audit documents adapated from Govwiki.

Updated