Hydrology
Drawn directly from OPM FedScope (June 2026), 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: 1,524 employees (0.1% of the federal civilian workforce) in the Physical Sciences Group family. At an average salary of $116,486 it pays near the federal average of $117,339, and headcount grew 0.3% from the prior period.
- Employees
- 1,524
- Share of workforce
- 0.1%
- Avg salary
- $116,486
- Avg tenure
- 17.1 yrs
FedScope read on Hydrology (dense series)
Federal agencies employ 1,524 people in the Hydrology occupation (OPM code 1315), accounting for 0.1% of the total federal civilian workforce of 1,953,300 for the June 2026 reporting window. Headcount in this occupation moved up by 0.3% versus the prior period, a modest but trackable signal for anyone considering this specialized federal career path.
Average tenure in Hydrology runs 17.1 years, a long average tenure, typical of career federal roles where employees stay through much of a full career before retirement. Pay averages $116,486 per year, up 0.1% from the prior period, a small shift, within the range of normal year-to-year rounding rather than a broad pay-table change.
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 in the Physical Sciences Group family.
Within the Physical Sciences Group family, Hydrology ranks #6 of 25 by headcount, accounting for 5.7% of the family's combined 26,960 employees. Its average salary ranks in the bottom half (25th percentile) of pay among Physical Sciences Group occupations.
Salary Context
How Hydrology pay compares to the federal average of $117,339
Occupation Average
$116,486
Federal Average
$117,339
vs. Federal Avg
-0.7%
Where Hydrology ranks on federal pay
Its average salary of $116,486 is higher than 65% of federal occupation series (350 of 541). The highlighted bar marks where Hydrology sits in the federal pay distribution.
Average-salary distribution across all 541 federal occupation series; Hydrology ranks higher than 65%.
Related Occupations in Physical Sciences Group
10 other occupations in the same family
| Occupation | Employees | Avg Salary | Avg LOS |
|---|---|---|---|
| General Physical Science | 8,297 | $145,078 | 14.6 yrs |
| Chemistry | 4,440 | $149,099 | 14.9 yrs |
| Meteorology | 2,494 | $123,942 | 15.9 yrs |
| Physics | 2,009 | $174,005 | 15.9 yrs |
| Physical Science Technician | 1,577 | $78,820 | 13.3 yrs |
| Hydrologic Technician | 1,356 | $76,077 | 12.9 yrs |
| Geology | 1,240 | $124,746 | 14 yrs |
| Health Physics | 746 | $146,649 | 16.4 yrs |
| Cartography | 487 | $120,890 | 16.3 yrs |
| Astronomy and Space Science | 416 | $177,819 | 18 yrs |
Nationwide peers near this dense headcount
Two peer sets for Hydrology outside the Physical Sciences Group family, on headcount and average salary axes that vary across all OPM occupation series.
Similar dense headcount
Nearest employee counts in other occupation families (1,524 here).
Similar average salary
Nearest average salaries in other occupation families ($116,486 here).
Key takeaways
- Hydrology pays near the federal average by 0.7% ($116,486 vs $117,339 federal-wide), at the 65th percentile for pay among 541 tracked occupation series.
- A smaller, specialized federal occupation by headcount: 1,524 employees, 0.1% of the federal civilian workforce, and headcount grew 0.3% from the prior period.
- According to OPM FedScope June 2026, Hydrology ranks #175 of 663 federal occupation series by headcount (the same employee_count ordering as our occupations directory).
- Within the Physical Sciences Group family, Hydrology ranks #6 of 25 by headcount, accounting for 5.7% of the family's combined 26,960 employees.
OPM FedScope and Federal Workforce Data figures are federal civilian headcounts, average salaries, and length-of-service statistics - not job-quality scores, hiring advice, or a live vacancy listing. A larger or higher-paid agency is not a better employer.