Company lists · Data refreshed November 2026

Top 25 Hydrology consulting services based in the United States

RevenueBase identified 1,300 company matches for hydrology consulting services associated with the United States as of November 2026 and tracks 59,326 professional contacts across them, including 29,094 with verified work emails. Houston is the largest hub.

This list covers company matches for hydrology consulting services associated with the United States, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed November 6, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list RevenueBase SmartSearch · Exact Recorded Nov 6, 2026 How this list was built
1,300Companies
59,326Contacts tracked
29,094Verified emails
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The 25 largest hydrology consulting services based in the United States

Ranked by team size
Top 25 of 1,300 company matches for hydrology consulting services based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Nov 6, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchPasadena, CA, United StatesHQ recorded Nov 6, 202610001+14,232 contacts →

Exact match

“Tetra Tech is the leader in water, environment and sustainable infrastructure, providing high-end technical and engineering services for projects worldwide.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
2Exact matchOlathe, NE, United StatesHQ recorded Nov 6, 20265,001-10,0006,576 contacts →

Exact match

“Terracon is a 100 percent employee-owned consulting engineering firm providing quality services to clients.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
3Exact matchWalnut Creek, CA, United StatesHQ recorded Nov 6, 20261,001-5,0002,553 contacts →

Exact match

“Headquartered in Walnut Creek, Calif, Brown and Caldwell is an employee-owned firm with 2,100+ professionals serving clients locally and globally from 52 locations.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
4Exact matchNew York, CO, United StatesHQ recorded Nov 6, 20261,001-5,0002,306 contacts →

Exact match

“As Hazen marks 75 years, we celebrate a legacy of absolute commitment to our clients while delivering the best technical work available anywhere.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
5Exact matchFort Worth, TX, United StatesHQ recorded Nov 6, 20261,001-5,0001,588 contacts →

Exact match

“Freese and Nichols is a professional planning, consulting and engineering firm serving clients across the United States.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
6Exact matchRockville, MD, United StatesHQ recorded Nov 6, 20261,001-5,0001,321 contacts →

Exact match

“Who is Apex?”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
7Exact matchSeattle, WA, United StatesHQ recorded Nov 6, 2026501-1,000923 contacts →

Exact match

“At Parametrix, we help our clients imagine what's possible.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
8Exact matchLafayette, MA, United StatesHQ recorded Nov 6, 20261,001-5,000876 contacts →

Exact match

“ATC Group Services LLC is now Atlas.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
9Exact matchEncinitas, CA, United StatesHQ recorded Nov 6, 2026501-1,000829 contacts →

Exact match

“Dudek is an environmental, planning, and engineering consulting firm.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
10Exact matchSan Francisco, OR, United StatesHQ recorded Nov 6, 2026501-1,000748 contacts →

Exact match

“ESA is a 100% employee-owned environmental consulting firm.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
11Exact matchSan Francisco, CA, United StatesHQ recorded Nov 6, 2026201-500593 contacts →

Exact match

“For over 100 years, Kennedy Jenks has provided engineering and scientific solutions for innovative water and environmental projects.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
12Exact matchLaramie, MT, United StatesHQ recorded Nov 6, 2026501-1,000583 contacts →

Exact match

“Headquartered in Laramie, Wyoming, Trihydro provides environmental consulting, engineering and surveying, air quality and process management, information technology, and water and…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
13Exact matchKennesaw, FL, United StatesHQ recorded Nov 6, 2026501-1,000541 contacts →

Exact match

“Established in 1996, NOVA was originally founded to provide Environmental Consulting, Geotechnical Engineering, and Construction Materials Testing and Inspection services to the…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
14Exact matchVentura, CA, United StatesHQ recorded Nov 6, 2026501-1,000509 contacts →

Exact match

“Rincon Consultants is a multidisciplinary environmental, planning, and advisory firm.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
15Exact matchSeattle, WA, United StatesHQ recorded Nov 6, 2026501-1,000503 contacts →

Exact match

“Headquartered in Seattle, Washington, Anchor QEA is a nationally recognized environmental science and engineering consulting firm specializing in aquatic, shoreline, and water…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
16Exact matchHarrisburg, PA, United StatesHQ recorded Nov 6, 2026201-500399 contacts →

Exact match

“HRG assists with the planning, design, and management of community infrastructure.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
17Exact matchIrvine, CA, United StatesHQ recorded Nov 6, 2026201-500360 contacts →

Exact match

“LSA is a diversified environmental, transportation, and community planning firm that evolved from a small consulting firm.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
18Exact matchGrand Forks, ND, United StatesHQ recorded Nov 6, 2026201-500358 contacts →

Exact match

“AE2S is a specialized civil/environmental consulting engineering firm that provides professional services and our unique brand of extreme client service to clients in the upper…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
19Exact matchOrlando, FL, United StatesHQ recorded Nov 6, 2026201-500320 contacts →

Exact match

“Ardaman & Associates, Inc.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
20Exact matchMarlborough, AZ, United StatesHQ recorded Nov 6, 202651-200318 contacts →

Exact match

“Tata & Howard is a 100% employee owned, award-winning, specialized consulting engineering firm dedicated to providing superior client service coupled with delivering…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
21Exact matchDavis, OR, United StatesHQ recorded Nov 6, 2026201-500296 contacts →

Exact match

“West Yost is a water-focused consulting engineering firm ranked by Fortune Magazine as one of the “Best Small and Medium Workplaces in Consulting and Professional Services” 2023 -…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
22Exact matchGainesville, NC, United StatesHQ recorded Nov 6, 2026201-500296 contacts →

Exact match

“For more than 30 years, WSSI has been the trusted partner in environmental, regulatory, cultural resources, and water resources engineering consulting.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
23Exact matchParlin, NJ, United StatesHQ recorded Nov 6, 2026201-500287 contacts →

Exact match

“CME Associates, with eight (8) office locations throughout New Jersey, provides a complete range of Environmental, Geotechnical, Engineering, Surveying and Planning services.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
24Exact matchAustin, FL, United StatesHQ recorded Nov 6, 2026201-500286 contacts →

Exact match

“Established in 1974, INTERA is a geosciences and engineering consulting firm focused on providing water resources and supply, environmental, mining, radioactive waste isolation…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
25Exact matchRosemont, IL, United StatesHQ recorded Nov 6, 2026201-500280 contacts →

Exact match

“Christopher B.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase

Showing 25 of 1,300 hydrology consulting services based in the United States

See the full list, filter by size, metro and specialty, and access 29,094 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Hydrology consulting services based in the United States at a glance

As of Nov 6, 2026
49.0%Verified-email coverage
45.6Average contacts per company
1-10Median size (employees)
1.8%Largest-city concentration · Houston
Nov 6, 2026Page data refreshed

Companies by employee count

1-10
726
11-50
403
51-200
117
201-500
25
501-1,000
10
1,001-5,000
10
5,001-10,000
3
10001+
2

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 1,300 companies.

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source
The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies
Company records associated with the United States whose business descriptions match “hydrology consulting services” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch
Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview
The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality
RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
Ranking
Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification
Every displayed company carries at least one verified work email. RevenueBase tracks 29,094 professional contacts with verified work emails across the full matched dataset. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh
This page's figures were pulled from the company graph on November 6, 2026. Lists refresh periodically as the graph is re-checked.
Record context
Company records and descriptions can change. Check the company's website for its current services and locations.

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “hydrology consulting services”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many hydrology consulting services are there based in the United States?

RevenueBase identified 1,300 company matches for hydrology consulting services associated with the United States as of November 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Tetra Tech tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most hydrology consulting services?

Houston leads with 23 company records, followed by Portland (22) and Denver (17).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 29,094 professional contacts with verified work emails tracked across these 1,300 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on November 6, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase SmartSearch, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.