Company lists · Data refreshed September 2026

Top 18 Environmental engineering firms based in Portland, United States

RevenueBase identified 31 environmental engineering firms headquartered in Portland, United States as of September 2026 and tracks 1,208 professional contacts across them, including 512 with verified work emails. Houston is the largest hub.

This list covers environmental engineering firms headquartered in Portland, United States, 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 16, 2026.

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 16, 2026 86% judged on-target in blind review
31Companies
1,208Contacts tracked
512Verified emails
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The 18 largest environmental engineering firms based in Portland, United States

Ranked by team size
Top 18 of 31 environmental engineering firms based in Portland, United States, ranked by team size, largest first. Data refreshed Sep 16, 2026. RevenueBase Smart Search rates how each company's information relates to environmental engineering 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 evidencePortland, OR, United StatesHQ checked Sep 16, 2026201-500744 contacts →

Partial evidence

“PAE provides mechanical and electrical engineering design, technology system design, energy modeling and analysis, and more.”

Source: RevenueBase Database · checked Sep 16, 2026
2Partial evidencePortland, ME, United StatesHQ checked Sep 16, 202611-50135 contacts →

Partial evidence

“Allied Engineering (AEI) is now Salas O'Brien.”

Source: RevenueBase Database · checked Sep 16, 2026
3Indirect evidencePortland, OR, United StatesHQ checked Sep 16, 202651-200101 contacts →

Indirect evidence

“Founded in Portland, Oregon in 1990, Harper Houf Peterson Righellis Inc.”

Source: RevenueBase Database · checked Sep 16, 2026
4Partial evidencePortland, OR, United StatesHQ checked Sep 16, 202651-20066 contacts →

Partial evidence

“GSI Water Solutions, Inc, is a specialized groundwater, environmental, and water resources consulting firm.”

Source: RevenueBase Database · checked Sep 16, 2026
5Indirect evidencePortland, ME, United StatesHQ checked Sep 16, 202611-5034 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 16, 2026
6Indirect evidencePortland, CT, United StatesHQ checked Sep 16, 202611-5033 contacts →

Indirect evidence

“Snyder Civil is a cohesive team of water system professionals based in central Connecticut.”

Source: RevenueBase Database · checked Sep 16, 2026
7Strong evidencePortland, CT, United StatesHQ checked Sep 16, 202611-5016 contacts →

Strong evidence

“RED Technologies, LLC (RED) is a privately held remediation, engineering and development contractor that provides waste transportation and disposal, environmental, and site…”

Source: RevenueBase Database · checked Sep 16, 2026
8Indirect evidencePortland, OR, United StatesHQ checked Sep 16, 202611-5010 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 16, 2026
9Partial evidencePortland, United StatesHQ checked Sep 16, 20261-107 contacts →

Partial evidence

“Northwest Watersheds LLC provides water resources engineering services to protect communities, restore habitat, and provide climate resiliency.”

Source: RevenueBase Database · checked Sep 16, 2026
10Indirect evidencePortland, OR, United StatesHQ checked Sep 16, 20261-106 contacts →

Indirect evidence

“Patrick D.”

Source: RevenueBase Database · checked Sep 16, 2026
11Strong evidencePortland, OR, United StatesHQ checked Sep 16, 20261-105 contacts →

Strong evidence

Environmental Management Systems, Inc.(EMS) Is a premier environmental consulting, engineering, and design firm headquartered in the Portland Metropolitan Area of Oregon.”

Source: RevenueBase Database · checked Sep 16, 2026
12Strong evidencePortland, ME, United StatesHQ checked Sep 16, 20261-104 contacts →

Strong evidence

“EHNS Partners is a small dedicated team specializing in environmental, health, and safety consulting and engineering.”

Source: RevenueBase Database · checked Sep 16, 2026
13Partial evidencePortland, OR, United StatesHQ checked Sep 16, 20261-104 contacts →

Partial evidence

“EES is a unique team of professional consultants specializing in environmental assessment, investigation, and cleanup services.”

Source: RevenueBase Database · checked Sep 16, 2026
14Partial evidencePortland, OR, United StatesHQ checked Sep 16, 202611-503 contacts →

Partial evidence

“KH2A Engineering, Inc.”

Source: RevenueBase Database · checked Sep 16, 2026
15Strong evidencePortland, OR, United StatesHQ checked Sep 16, 20261-103 contacts →

Strong evidence

“Aquarius Environmental is an environmental engineering and consulting firm specializing in water related design, treatment, and compliance.”

Source: RevenueBase Database · checked Sep 16, 2026
16Partial evidencePortland, OR, United StatesHQ checked Sep 16, 20261-102 contacts →

Partial evidence

“Ferment Service provides fractional and T&M engineering consulting to CPG manufacturers, food and beverage producers, and industrial clients.”

Source: RevenueBase Database · checked Sep 16, 2026
17Partial evidencePortland, ME, United StatesHQ checked Sep 16, 20261-101 contacts →

Partial evidence

“McFadden Environmental is an environmental consulting firm based in Portland Maine.”

Source: RevenueBase Database · checked Sep 16, 2026
18Partial evidencePortland, OR, United StatesHQ checked Sep 16, 20261-101 contacts →

Partial evidence

“I specialize in helping my clients navigate the ever-evolving landscape of environmental regulation and property remediation, bringing technical expertise, critical thinking, and…”

Source: RevenueBase Database · checked Sep 16, 2026

Showing 18 of 31 environmental engineering firms based in Portland, United States

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Environmental engineering firms based in Portland, United States at a glance

As of Sep 16, 2026
42.4%Verified-email coverage
39.0Average contacts per company
1-10Median size (employees)
445.2%Largest-city concentration · Houston
Sep 16, 2026Page data refreshed

Companies by employee count

1-10
17
11-50
11
51-200
2
201-500
1

Email recency for this list is measured across the whole United States list rather than for Portland, so it is reported there. Company counts and contact totals on this page are exact for Portland, over 31 companies.

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 environmental engineering 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.
What qualifies
Companies headquartered in Portland, United States whose own description of what they do matches “environmental engineering 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 environmental engineering 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 environmental engineering firms, and records with no verified work email. Companies headquartered outside Portland are excluded even when they keep an office there.
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, 512 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 16, 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.

Environmental engineering firms by metro in the United States

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 environmental engineering 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 environmental engineering firms are there based in Portland, United States?

RevenueBase identified 31 environmental engineering firms headquartered in Portland, United States 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?

PAE, headquartered in Portland, tops this list with the largest team on record.

Which city has the most environmental engineering firms?

Houston leads with 138 headquartered companies, followed by New York (101) and Austin (73).

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 512 verified decision-maker contacts tracked across these 31 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 16, 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.