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OPM FedScope March 2025 Physical Sciences Group

Hydrology

Drawn directly from OPM FedScope (March 2025), this page tracks headcount, average salary, tenure, and pay comparison for the Hydrology occupation series (code 1315).

The verdict

Hydrology is a smaller, specialized federal occupation: 1,903 employees (0.1% of the federal civilian workforce) in the Physical Sciences Group family. At an average salary of $114,328 it pays near the federal average of $109,869, and headcount declined 1.6% from the prior period.

Employees
1,903
Share of workforce
0.1%
Avg salary
$114,328
Avg tenure
16.6 yrs

What the Numbers Say About Hydrology

Federal agencies employ 1,903 people in the Hydrology occupation (OPM code 1315), accounting for 0.1% of the total federal civilian workforce of 2,289,472 for the March 2025 reporting window. Headcount in this occupation moved down by -1.6% versus the prior period, a modest but trackable signal for anyone considering this specialized federal career path.

Average tenure in Hydrology runs 16.6 years, a long average tenure, typical of career federal roles where employees stay through much of a full career before retirement. Pay averages $114,328 per year, 4.1% above the $109,869 federal civilian average and up 2.3% from the prior period, a broad shift as locality pay tables and grade-level adjustments moved through the workforce.

Code 13, the Physical Sciences Group family, is where the federal government classifies Hydrology alongside 24 related occupations. Candidates browsing USAJOBS for Hydrology postings should also review these sibling occupations, since federal hiring managers often cross-post positions across closely related codes when recruitment is difficult. All figures here come directly from OPM FedScope Employment Cubes, the same official source referenced in federal workforce planning, budget justifications, and GAO reports.

Within the Physical Sciences Group family, Hydrology ranks #5 of 25 by headcount, accounting for 5.9% of the family's combined 32,337 employees. Its average salary ranks in the bottom half (28th percentile) of pay among Physical Sciences Group occupations.

Employees

1,903

-1.6% from prior period

Average Salary

$114,328

+2.3%

Avg Length of Service

16.6 yrs

Occupation Family

Physical Sciences Group

Salary Context

How Hydrology pay compares to the federal average of $109,869

Occupation Average

$114,328

Federal Average

$109,869

vs. Federal Avg

+4.1%

Where Hydrology ranks on federal pay

Its average salary of $114,328 is higher than 72% of federal occupation series (456 of 634). The highlighted bar marks where Hydrology sits in the federal pay distribution.

$16,074132$63,787308$111,499167$159,21223$206,9242$254,6372
Distribution of average salary across all 634 federal occupation series (OPM FedScope) - Hydrology is in the highlighted range.

Average-salary distribution across all 634 federal occupation series; Hydrology ranks higher than 72%.

Source: OPM FedScope Employment Cubes As of March 2025

10 other occupations in the same family

Occupation Employees Avg Salary
General Physical Science 10,323 $138,591
Chemistry 5,165 $140,120
Meteorology 2,727 $123,622
Physics 2,312 $155,280
Physical Science Technician 1,794 $83,137
Hydrologic Technician 1,636 $71,877
Geology 1,469 $117,766
Health Physics 888 $130,197
Cartography 579 $114,969
Navigational Information 504 $144,773

Frequently Asked Questions

How many federal employees work as Hydrology?
Hydrology employs 1,903 federal workers as of March 2025, a 0.1% share of the total federal civilian workforce.
What is the average salary for Hydrology in the federal government?
The average salary for Hydrology in the federal government is $114,328 per year, which is 4.1% above the overall federal average of $109,869.
What occupation family does Hydrology belong to?
Hydrology (code 1315) belongs to the Physical Sciences Group family (code 13). There are 25 occupations in this family.
What is the average length of service for Hydrology?
Hydrology employees stay an average of 16.6 years, compared with the 11.8-year federal-wide average.
Is the Hydrology workforce growing or shrinking?
A decline of 1.6% from the prior period put the Hydrology occupation at 1,903 employees, down roughly 30 positions.
How does Hydrology pay compare to private sector salaries?
The federal average salary for Hydrology is $114,328, 4.1% above the $109,869 federal-wide average. For private-sector benchmarks in this field, see the BLS Occupational Employment and Wage Statistics (OEWS) program.

Data Source: U.S. Office of Personnel Management (OPM) FedScope Employment Cubes, March 2025. Federal civilian non-seasonal full-time and part-time employees. Data does not include military personnel, postal workers, or intelligence agency staff. Last updated: 2026-03-10.

Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainGovJobs

PlainGovJobs is rendered directly from OPM FedScope federal-workforce data, no number is typed in by an editor. This page draws directly on OPM FedScope occupation-level employment records. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.