Company lists · Data refreshed November 2026

Top 25 Wastewater treatment engineering consultants worldwide

Name: Wastewater treatment engineering consultants worldwide
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Nov 6, 2026 13,882 companies tracked

RevenueBase identified 13,882 company matches for wastewater treatment engineering consultants worldwide as of November 2026 and tracks 287,544 professional contacts across them, including 93,411 with verified work emails. The United States is the largest market and Tehran the largest hub.

This list covers company matches for wastewater treatment engineering consultants worldwide, 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. Country and city lists for wastewater treatment engineering consultants follow the table.

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

13,882Companies

287,544Contacts tracked

93,411Verified emails

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The 25 largest wastewater treatment engineering consultants worldwide

Ranked by team size

Top 25 of 13,882 company matches for wastewater treatment engineering consultants worldwide, 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.
#	Company	RevenueBase SmartSearch	Headquarters	Employees	Contacts
1	Tetra Tech	Exact match	Pasadena, CA, United StatesHQ recorded Nov 6, 2026	10001+	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
2	CDM Smith	Exact match	Boston, MA, United StatesHQ recorded Nov 6, 2026	5,001-10,000	8,143 contacts →
	Exact match “CDM Smith is shaping what’s next, now, with world class solutions in water, environment, transportation and energy to public and private clients worldwide.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
3	Terracon	Exact match	Olathe, NE, United StatesHQ recorded Nov 6, 2026	5,001-10,000	6,576 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
4	ION Exchange India LTD	Exact match	Mumbai, IndiaHQ recorded Nov 6, 2026	1,001-5,000	4,010 contacts →
	Exact match “At Ion Exchange India, we bring you total environment solutions - water treatment, liquid waste treatment & recycle, air pollution control, solid & hazardous waste management and…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
5	Golder	Exact match	Las Condes, CanadaHQ recorded Nov 6, 2026	5,001-10,000	3,239 contacts →
	Exact match “Golder was acquired by WSP.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
6	Geosyntec Consultants	Exact match	Boca Raton, FL, United StatesHQ recorded Nov 6, 2026	1,001-5,000	2,553 contacts →
	Exact match “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…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
7	Brown And Caldwell	Exact match	Walnut Creek, CA, United StatesHQ recorded Nov 6, 2026	1,001-5,000	2,553 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
8	Hazen And Sawyer	Exact match	New York, CO, United StatesHQ recorded Nov 6, 2026	1,001-5,000	2,306 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
9	Olsson	Exact match	Lincoln, AR, United StatesHQ recorded Nov 6, 2026	1,001-5,000	2,289 contacts →
	Exact match “Olsson is an engineering firm made up of people who craft expert solutions and designs that improve communities.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
10	Civil & Environmental Consultants, INC	Exact match	Moon Township, MO, United StatesHQ recorded Nov 6, 2026	1,001-5,000	2,276 contacts →
	Exact match “Civil & Environmental Consultants, Inc.(CEC) provides comprehensive market-oriented consulting services that advance the strategic business objectives of its clients.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
11	Providence	Exact match	Baton Rouge, LA, United StatesHQ recorded Nov 6, 2026	n/a	2,268 contacts →
	Exact match “Providence is an employee-owned engineering and environmental consulting firm.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
12	Burns & Mcdonnell India	Exact match	Vikhroli West, IndiaHQ recorded Nov 6, 2026	1,001-5,000	1,874 contacts →
	Exact match “At Burns & McDonnell India, we are a diverse team of talented engineers with multidiscipline design and consultancy working across sectors in critical infrastructure: oil and gas…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
13	Carollo Engineers	Exact match	Walnut Creek, NV, United StatesHQ recorded Nov 6, 2026	1,001-5,000	1,837 contacts →
	Exact match “For more than 90 years, Carollo Engineers has been dedicated exclusively to water and wastewater solutions.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
14	CHA Consulting, INC	Exact match	Albany, NH, United StatesHQ recorded Nov 6, 2026	1,001-5,000	1,780 contacts →
	Exact match “CHA Consulting, Inc.(CHA) is an innovative, full-service engineering, design, consulting, and program/construction management firm providing a wide range of technology-enhanced…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
15	GEI Consultants, INC	Exact match	Woburn, MA, United StatesHQ recorded Nov 6, 2026	1,001-5,000	1,675 contacts →
	Exact match Recorded description not available. Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
16	Freese And Nichols	Exact match	Fort Worth, TX, United StatesHQ recorded Nov 6, 2026	1,001-5,000	1,588 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
17	Apex Companies	Exact match	Rockville, MD, United StatesHQ recorded Nov 6, 2026	1,001-5,000	1,321 contacts →
	Exact match “Who is Apex?” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
18	Volvo Eicher Commerical Vehical Limited	Exact match	Dhar, IndiaHQ recorded Nov 6, 2026	n/a	1,235 contacts →
	Exact match “Volvo Eicher Commerical Vehical Limited Service Provider of waste water recycling systems, drinking water plant & industrial water treatment in Indore, Madhya Pradesh.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
19	Barr Engineering CO	Exact match	Minneapolis, NV, United StatesHQ recorded Nov 6, 2026	1,001-5,000	1,146 contacts →
	Exact match “Barr provides engineering and environmental consulting services to clients across the Midwest, throughout the Americas, and around the world.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
20	Trinity Consultants	Exact match	Dallas, TX, United StatesHQ recorded Nov 6, 2026	1,001-5,000	1,114 contacts →
	Exact match “Trinity Consultants is a global team of specialists helping organizations solve complex challenges in environmental compliance, ecological protection, infrastructure and built…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
21	Associated Engineering	Exact match	Edmonton, MB, CanadaHQ recorded Nov 6, 2026	501-1,000	1,084 contacts →
	Exact match “At Associated, we are passionate about building communities that are vibrant, healthy and resilient and support economic growth.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
22	WSP Chile Y Argentina	Exact match	Vitacura, ChileHQ recorded Nov 6, 2026	10001+	1,079 contacts →
	Exact match “WSP en una empresa líder en servicios profesionales de consultoría en recursos hídricos, ingeniería, medio ambiente y sustentabilidad.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
23	Cardno	Exact match	Fortitude Valley, CO, AustraliaHQ recorded Nov 6, 2026	1,001-5,000	1,059 contacts →
	Exact match “Cardno is now officially Stantec.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
24	GAI Consultants, INC	Exact match	Homestead, PA, United StatesHQ recorded Nov 6, 2026	501-1,000	1,027 contacts →
	Exact match “Transforming ideas into reality® since 1958, GAI Consultants is an engineering, planning, and environmental consulting firm that provides customized solutions and local expertise…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
25	MWH Treatment	Exact match	Stockport, United KingdomHQ recorded Nov 6, 2026	1,001-5,000	971 contacts →
	Exact match “MWH Treatment is a leading Design and Build non-infrastructure solution provider in the UK water sector, with a water sector heritage dating back to 1820.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase

RevenueBase SmartSearch

Describe a niche business in your own words. RevenueBase SmartSearch compares the meaning of your description with company business descriptions compiled in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit.

This list uses Exact for “wastewater treatment engineering consultants”. Each Exact match badge shows membership in that saved search; it is not an individual similarity score or a service-quality rating. Recorded descriptions are shown where available.

Showing 25 of 13,882 wastewater treatment engineering consultants worldwide

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Wastewater treatment engineering consultants worldwide at a glance

As of Nov 6, 2026

32.5%Verified-email coverage

20.7Average contacts per company

11-50Median size (employees)

0.9%Largest-city concentration · Tehran

Nov 6, 2026Page data refreshed

Companies by employee count

1-10

6,064

11-50

5,003

51-200

1,833

201-500

495

501-1,000

160

1,001-5,000

103

5,001-10,000

10001+

Email recency is reported on each country list linked below.

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.
Coverage: Every country. Country and city lists for wastewater treatment engineering consultants are linked below.
What qualifies: Company records worldwide whose business descriptions match “wastewater treatment engineering consultants” 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. 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 93,411 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.

Wastewater treatment engineering consultants by location

63 lists · largest first

Every Wastewater treatment engineering consultants 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 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 “wastewater treatment engineering consultants”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many wastewater treatment engineering consultants are there worldwide?

RevenueBase identified 13,882 company matches for wastewater treatment engineering consultants worldwide 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 country has the most wastewater treatment engineering consultants?

The United States leads with 2,645 companies, followed by India (1,271) and Brazil (896). Every wastewater treatment engineering consultants list by country and city is linked on this page.

Which city has the most wastewater treatment engineering consultants?

Tehran leads with 130 company records, followed by Pune (126) and Sao Paulo (112).

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 93,411 professional contacts with verified work emails tracked across these 13,882 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.