Company lists · Data refreshed September 2026

Top 25 Marine environmental consulting firms worldwide

RevenueBase identified 18,100 marine environmental consulting firms worldwide as of September 2026 and tracks 289,762 professional contacts across them, including 82,856 with verified work emails. The United States is the largest market and Singapore the largest hub.

This list covers marine environmental 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 marine environmental 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.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 28, 2026 86% judged on-target in blind review
18,100Companies
289,762Contacts tracked
82,856Verified emails
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The 25 largest marine environmental consulting firms worldwide

Ranked by team size
Top 25 of 18,100 marine environmental consulting firms worldwide, ranked by team size, largest first. Data refreshed Sep 28, 2026. RevenueBase Smart Search rates how each company's information relates to marine environmental consulting firms: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Partial evidenceOlathe, KS, United StatesHQ checked Sep 28, 20265,001-10,0006,113 contacts →

Partial evidence

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

Source: RevenueBase Database · checked Sep 28, 2026
2Strong evidenceBeveren-kruibeke-zwijndrecht, BelgiumHQ checked Sep 28, 20265,001-10,0004,395 contacts →

Strong evidence

“DEME (Euronext Brussels: DEME) is a leading contractor in the fields of offshore energy, dredging and marine infrastructure, and environmental remediation.”

Source: RevenueBase Database · checked Sep 28, 2026
3Partial evidence3063 Nh, NetherlandsHQ checked Sep 28, 20265,001-10,0004,364 contacts →

Partial evidence

“Van Oord is a leading international marine contractor focusing on dredging, infrastructure and offshore energy projects.”

Source: RevenueBase Database · checked Sep 28, 2026
4Indirect evidenceVancouver, BC, CanadaHQ checked Sep 28, 20265,001-10,0003,167 contacts →

Indirect evidence

“Golder was acquired by WSP.”

Source: RevenueBase Database · checked Sep 28, 2026
5Indirect evidenceRio De Janeiro, BrazilHQ checked Sep 28, 20261,001-5,0002,922 contacts →

Indirect evidence

“Somos a Bram Offshore Transportes Marítimos, a maior empresa representante do Grupo Edison Chouest Offshore no Brasil, reconhecida como o fornecedor de soluções de transporte…”

Source: RevenueBase Database · checked Sep 28, 2026
6Indirect evidenceWalnut Creek, CA, United StatesHQ checked Sep 28, 20261,001-5,0002,473 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, 2026
7Strong evidenceBoca Raton, FL, United StatesHQ checked Sep 28, 20261,001-5,0002,393 contacts →

Strong 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, 2026
8Partial evidenceAl-khobar, Saudi ArabiaHQ checked Sep 28, 20261,001-5,0002,312 contacts →

Partial evidence

“Zamil Offshore Services Company has been offering diversified offshore and marine support services to the oil and gas industry since 1977.”

Source: RevenueBase Database · checked Sep 28, 2026
9Indirect evidenceBrazilHQ checked Sep 28, 2026n/a2,224 contacts →

Indirect evidence

“Rov company.”

Source: RevenueBase Database · checked Sep 28, 2026
10Indirect evidenceSingaporeHQ checked Sep 28, 20265,001-10,0001,915 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 28, 2026
11Indirect evidenceNiterói, BrazilHQ checked Sep 28, 20261,001-5,0001,847 contacts →

Indirect evidence

“O Grupo CBO é uma das maiores empresas de apoio marítimo do Brasil.”

Source: RevenueBase Database · checked Sep 28, 2026
12Strong evidencePhoenix, AZ, United StatesHQ checked Sep 28, 20261,001-5,0001,629 contacts →

Strong evidence

“Founded on a commitment to sound science and creative solutions, SWCA is a leader in environmental and management consulting services.”

Source: RevenueBase Database · checked Sep 28, 2026
13Partial evidenceLittle Rock, AR, United StatesHQ checked Sep 28, 20261,001-5,0001,529 contacts →

Partial evidence

“Onterris (formerly Montrose Environmental Group) was one of the first to see environmental responsibility as not just an imperative but as a strategic asset.”

Source: RevenueBase Database · checked Sep 28, 2026
14Indirect evidenceHørsholm, DenmarkHQ checked Sep 28, 20261,001-5,0001,427 contacts →

Indirect evidence

“There is no substitute for water.”

Source: RevenueBase Database · checked Sep 28, 2026
15Indirect evidenceRio De Janeiro, BrazilHQ checked Sep 28, 2026201-5001,407 contacts →

Indirect evidence

“With more than 50 years of legacy, Maersk Supply Service celebrates a new important milestone: from November 1st, our headquarters are officially located in Brazil.”

Source: RevenueBase Database · checked Sep 28, 2026
16Partial evidenceHong KongHQ checked Sep 28, 2026501-1,0001,313 contacts →

Partial evidence

“First established in Shanghai in 1903, Wallem Group has a 120-year maritime heritage with a presence in 19 countries globally.”

Source: RevenueBase Database · checked Sep 28, 2026
17Indirect evidenceHøjbjerg, DenmarkHQ checked Sep 28, 2026n/a1,176 contacts →

Indirect evidence

“Miljø er vores kernekompetence og vores ansvar.”

Source: RevenueBase Database · checked Sep 28, 2026
18Partial evidenceTampa, FL, United StatesHQ checked Sep 28, 20261,001-5,0001,139 contacts →

Partial evidence

“At Verdantas, we blend engineering and environmental science together with advanced technology and world-renowned labs to create solutions with the big picture in mind.”

Source: RevenueBase Database · checked Sep 28, 2026
19Indirect evidenceRockville, MD, United StatesHQ checked Sep 28, 20261,001-5,0001,137 contacts →

Indirect evidence

“Who is Apex?”

Source: RevenueBase Database · checked Sep 28, 2026
20Indirect evidenceMakati City, PhilippinesHQ checked Sep 28, 2026501-1,0001,102 contacts →

Indirect evidence

“People at the heart.”

Source: RevenueBase Database · checked Sep 28, 2026
21Strong evidenceMinneapolis, MN, United StatesHQ checked Sep 28, 20261,001-5,0001,088 contacts →

Strong 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, 2026
22Partial evidenceLaksevåg, NorwayHQ checked Sep 28, 20261,001-5,0001,031 contacts →

Partial evidence

“Shearwater is a global marine geoscience and technology business.”

Source: RevenueBase Database · checked Sep 28, 2026
23Indirect evidenceVitacura, ChileHQ checked Sep 28, 202610001+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, 2026
24Partial evidenceDallas, TX, United StatesHQ checked Sep 28, 20261,001-5,000961 contacts →

Partial evidence

“Trinity Consultants is a global team of experts helping organizations solve complex challenges in environmental compliance, ecological protection, infrastructure performance, and…”

Source: RevenueBase Database · checked Sep 28, 2026
25Partial evidenceDecatur, AL, United StatesHQ checked Sep 28, 20261,001-5,000956 contacts →

Partial evidence

“Alliance is a new kind of environmental services company-powered by innovation, focused on service, and committed to client success.”

Source: RevenueBase Database · checked Sep 28, 2026

Showing 25 of 18,100 marine environmental consulting firms worldwide

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Marine environmental consulting firms worldwide at a glance

As of Sep 28, 2026
28.6%Verified-email coverage
16.0Average contacts per company
1-10Median size (employees)
1.2%Largest-city concentration · Singapore
Sep 28, 2026Page data refreshed

Companies by employee count

1-10
10,378
11-50
5,435
51-200
1,550
201-500
413
501-1,000
123
1,001-5,000
90
5,001-10,000
12
10001+
18

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 marine environmental 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 marine environmental consulting firms are linked below.
What qualifies
Companies worldwide whose own description of what they do matches “marine environmental 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 marine environmental 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 marine environmental 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, 82,856 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.

Marine environmental consulting firms by location

88 lists · largest first

Every Marine environmental consulting firms list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.

Countries

Cities

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 marine environmental 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 marine environmental consulting firms are there worldwide?

RevenueBase identified 18,100 marine environmental 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?

Terracon, headquartered in Olathe, tops this list with the largest team on record.

Which country has the most marine environmental consulting firms?

The United States leads with 3,248 companies, followed by Brazil (1,769) and the United Kingdom (984). Every marine environmental consulting firms list by country and city is linked on this page.

Which city has the most marine environmental consulting firms?

Singapore leads with 221 headquartered companies, followed by Rio De Janeiro (158) and Sao Paulo (157).

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 82,856 verified decision-maker contacts tracked across these 18,100 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.