Company lists · Data refreshed September 2026
Top 25 Hydrogeology consulting firms worldwide
RevenueBase identified 6,636 hydrogeology consulting firms worldwide as of September 2026 and tracks 133,515 professional contacts across them, including 52,808 with verified work emails. The United States is the largest market and Belo Horizonte the largest hub.
This list covers hydrogeology consulting firms worldwide, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 28, 2026. Country and city lists for hydrogeology consulting firms follow the table.
Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, 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.
The 25 largest hydrogeology consulting firms worldwide
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 12,999 contacts → | ||||
Indirect evidence “Tetra Tech is the leader in water, environment and sustainable infrastructure, providing high-end technical and engineering services for projects worldwide.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 2 | 6,113 contacts → | ||||
Partial evidence “Terracon is a 100 percent employee-owned consulting engineering firm providing quality services to clients.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 3 | 2,473 contacts → | ||||
Indirect evidence “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.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 4 | 2,393 contacts → | ||||
Partial evidence “Geosyntec is a consulting and engineering firm that works with private and public sector clients to address new ventures and complex problems involving our environment, natural…” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 5 | 2,259 contacts → | ||||
Partial evidence “SRK Consulting is an independent, international group providing specialised consultancy services.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 6 | 2,210 contacts → | ||||
Partial evidence “ECS Group of Companies is a Chantilly, VA-based consulting engineering firm.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 7 | 2,100 contacts → | ||||
Indirect evidence “As Hazen marks 75 years, we celebrate a legacy of absolute commitment to our clients while delivering the best technical work available anywhere.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 8 | 1,604 contacts → | ||||
Indirect evidence Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 9 | 1,496 contacts → | ||||
Partial evidence “Freese and Nichols is a professional planning, consulting and engineering firm serving clients across the United States.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 10 | 1,427 contacts → | ||||
Indirect evidence “There is no substitute for water.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 11 | 1,231 contacts → | ||||
Partial evidence “Knight Piésold is an employee-owned, global consulting firm providing specialist services to the mining, power, water resources, and infrastructure industries.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 12 | 1,137 contacts → | ||||
Indirect evidence “Who is Apex?” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 13 | 1,088 contacts → | ||||
Partial evidence “Barr provides engineering and environmental consulting services to clients across the Midwest, throughout the Americas, and around the world.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 14 | 988 contacts → | ||||
Indirect evidence “WSP en una empresa líder en servicios profesionales de consultoría en recursos hídricos, ingeniería, medio ambiente y sustentabilidad.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 15 | 880 contacts → | ||||
Indirect evidence “Founded in 1964 as a soils and foundations specialty consultant, GZA GeoEnvironmental, Inc.(GZA) has grown into a full-service company providing its clients with highly…” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 16 | 871 contacts → | ||||
Partial evidence “KCB is a global engineering, geosciences, and environmental consulting firm driven by Passion, Integrity and a commitment to Excellence.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 17 | 798 contacts → | ||||
Partial evidence “BGC Engineering is an international consulting firm that provides professional services in applied earth sciences.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 18 | 795 contacts → | ||||
Partial evidence “Dudek is an environmental, planning, and engineering consulting firm.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 19 | 709 contacts → | ||||
Indirect evidence “Over six decades offering our consultancy services locally and internationally, based on ethical principles and commitments, always through honest, socially responsible actions…” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 20 | 707 contacts → | ||||
Indirect evidence “Schnabel is a trusted partner in building the foundation for project success.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 21 | 588 contacts → | ||||
Indirect evidence “Sondotécnica was founded in 1954.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 22 | 582 contacts → | ||||
Indirect evidence “Founded in 1968, Raba Kistner Inc.” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 23 | 577 contacts → | ||||
Partial evidence “Headquartered in Laramie, Wyoming, Trihydro provides environmental consulting, engineering and surveying, air quality and process management, information technology, and water and…” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 24 | 518 contacts → | ||||
Partial evidence “Established in 1996, NOVA was originally founded to provide Environmental Consulting, Geotechnical Engineering, and Construction Materials Testing and Inspection services to the…” Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
| 25 | 480 contacts → | ||||
Indirect evidence Source: RevenueBase Database · checked Sep 28, 2026Thanks. The Data Team will review it. | |||||
RevenueBase Smart Search
RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: hydrogeology consulting firms. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.
- Strong evidence
- The company's own public description of its business names hydrogeology consulting firms.
- Partial evidence
- Its own public description names part of hydrogeology consulting firms, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name hydrogeology consulting firms. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.
RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.
Showing 25 of 6,636 hydrogeology consulting firms worldwide
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Hydrogeology consulting firms worldwide at a glance
As of Sep 28, 2026Companies by employee count
Email recency is reported on each country list linked below.
How this list was built
Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among hydrogeology consulting firms, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.
- Source
- The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
- Coverage
- Every country. Country and city lists for hydrogeology consulting firms are linked below.
- What qualifies
- Companies worldwide whose own description of what they do matches “hydrogeology consulting firms”. Matching reads each company's description, not its industry code or its name.
- RevenueBase Smart Search
- RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names hydrogeology consulting firms), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
- What we exclude
- Companies whose own description does not clearly place them among hydrogeology consulting firms, and records with no verified work email.
- Match quality
- In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
- 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 listed company carries at least one verified work email, 52,808 across the full list. 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 September 28, 2026. Lists refresh periodically as the graph is re-checked.
- Corrections
- Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.
Hydrogeology consulting firms by location
33 lists · largest firstEvery Hydrogeology consulting firms list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.
Countries
- Hydrogeology consulting firms based in the United States1,697
- Hydrogeology consulting firms based in Brazil471
- Hydrogeology consulting firms based in Canada357
- Hydrogeology consulting firms based in France301
- Hydrogeology consulting firms based in Germany258
- Hydrogeology consulting firms based in Australia256
- Hydrogeology consulting firms based in Italy181
- Hydrogeology consulting firms based in Chile178
- Hydrogeology consulting firms based in Spain151
- Hydrogeology consulting firms based in the United Kingdom148
- Hydrogeology consulting firms based in Colombia128
- Hydrogeology consulting firms based in India123
- Hydrogeology consulting firms based in South Africa118
- Hydrogeology consulting firms based in Peru106
- Hydrogeology consulting firms based in Türkiye93
- Hydrogeology consulting firms based in Switzerland92
- Hydrogeology consulting firms based in Mexico75
- Hydrogeology consulting firms based in Argentina64
- Hydrogeology consulting firms based in the Netherlands64
- Hydrogeology consulting firms based in Indonesia58
- Hydrogeology consulting firms based in New Zealand41
- Hydrogeology consulting firms based in Portugal39
- Hydrogeology consulting firms based in Belgium34
- Hydrogeology consulting firms based in Austria33
- Hydrogeology consulting firms based in Sweden32
- Hydrogeology consulting firms based in Norway26
Cities
- Hydrogeology consulting firms based in Belo Horizonte, Brazil92
- Hydrogeology consulting firms based in Calgary, Canada60
- Hydrogeology consulting firms based in Houston, United States51
- Hydrogeology consulting firms based in Sao Paulo, Brazil46
- Hydrogeology consulting firms based in Santiago, Chile41
- Hydrogeology consulting firms based in Denver, United States33
- Hydrogeology consulting firms based in Porto Alegre, Brazil25
Frequently asked
What is RevenueBase Smart Search?
RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names hydrogeology consulting firms, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.
How many hydrogeology consulting firms are there worldwide?
RevenueBase identified 6,636 hydrogeology consulting firms worldwide as of September 2026, matched on each company's own description of what it does rather than its industry code.
What is the largest company on this list?
Tetra Tech, headquartered in Pasadena, tops this list with the largest team on record.
Which country has the most hydrogeology consulting firms?
The United States leads with 1,697 companies, followed by Brazil (471) and Canada (357). Every hydrogeology consulting firms list by country and city is linked on this page.
Which city has the most hydrogeology consulting firms?
Belo Horizonte leads with 92 headquartered companies, followed by Calgary (60) and Houston (51).
How do I get contact information for these companies?
A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 52,808 verified decision-maker contacts tracked across these 6,636 companies.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 28, 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 Smart Search, 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.