Company lists · Data refreshed September 2026

Top 21 Environmental engineering firms based in Washington, United States

Name: Environmental engineering firms based in Washington, United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 16, 2026 32 companies tracked

RevenueBase identified 32 company matches for environmental engineering firms associated with Washington, United States as of September 2026 and tracks 383 professional contacts across them, including 199 with verified work emails. Across the United States, Houston is the largest hub for this category (138 companies); Washington has 32.

This list covers company matches for environmental engineering firms associated with Washington, 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 September 16, 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 Sep 16, 2026 How this list was built

32Companies

383Contacts tracked

199Verified emails

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The 21 largest environmental engineering firms based in Washington, United States

Ranked by team size

Top 21 of 32 company matches for environmental engineering firms based in Washington, United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 16, 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	Delon Hampton & Associates, Chartered	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	51-200	72 contacts →
	Exact match “Delon Hampton & Associates, Chartered (DHA), is a professional consulting engineering firm specializing in civil and structural engineering, as well as program and construction…” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
2	Peer Consultants, P.C	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	51-200	71 contacts →
	Exact match “In 1978, PEER was established under Dr.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
3	Moody And Associates, INC	Exact match	Washington, PA, United StatesHQ recorded Sep 16, 2026	51-200	54 contacts →
	Exact match Recorded description not available. Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
4	SZ PM Consultants, INC	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	11-50	24 contacts →
	Exact match Recorded description not available. Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
5	Bfa, INC	Exact match	Washington, MO, United StatesHQ recorded Sep 16, 2026	11-50	19 contacts →
	Exact match “BFA is a consulting civil engineering firm located in downtown Washington, Missouri.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
6	Foxxstem	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	11-50	19 contacts →
	Exact match “FOXXSTEM is a professional engineering consulting firm that inspires and creates infrastructure that connects people to communities and communities to opportunities for better…” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
7	The Clark Group LLC	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	11-50	19 contacts →
	Exact match “The Clark Group is an environmental policy consulting firm that provides a broad range of services to government, private and nonprofit clients.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
8	Harshman CE Group, LLC	Exact match	Washington, PA, United StatesHQ recorded Sep 16, 2026	11-50	19 contacts →
	Exact match “We are a full service Professional Engineering consulting firm providing civil site and infrastructure design, professional land surveying, facility design, and permitting support…” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
9	Brockerhoff Environmental Services	Exact match	Washington, NJ, United StatesHQ recorded Sep 16, 2026	11-50	9 contacts →
	Exact match “Since 2007, BES has combined innovative technology with cost-effective and focused strategies to deliver effective remediation services for our clients.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
10	Designgreen, LLC	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	1-10	7 contacts →
	Exact match “Designgreen, LLC is a woman-owned engineering firm located in the District of Columbia offering professional consulting and technical support services for small and large projects…” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
11	DRM International, INC	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	1-10	7 contacts →
	Exact match “DRM International, Inc,(DRM) is a leading DIsadvantaged Business Enterprise (DBE) professional engineering consulting firm offering engineering, architectural, planning…” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
12	Modulus	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	51-200	7 contacts →
	Exact match “Modulus is a minority-owned MBE, SBE and DBE consulting firm based in Washington, DC, which provides services to the Northeast Region.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
13	Huska & Horgan Engineering	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	1-10	6 contacts →
	Exact match “Founded in 2016, Huska & Horgan Engineering, formerly Huska Consulting, is a top-notch civil engineering firm serving the greater Washington, D.C.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
14	Grotheer & CO	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	11-50	5 contacts →
	Exact match “GROTHEER & CO, a small business located in Washington, DC, has been practicing professional engineering since 1954, and has completed thousands of projects for local and federal…” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
15	Deborah Brosnan & Associates	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	1-10	4 contacts →
	Exact match “Leading and innovative company that finding solutions, bridging gaps and driving positive action for clients and the planet.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
16	Greening Urban LLC	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	1-10	3 contacts →
	Exact match “Greening Urban is a civil engineering firm with built projects in Washington, D.C; Maryland; and Virginia.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
17	Ceed Civil Engineering	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	11-50	3 contacts →
	Exact match “CEED CIVIL ENGINEERING is a civil engineering and environmental engineering design firm serving Fairfax, VA, and entire Northern Virginia and DC Metro Area.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
18	Empower Infrastructure	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	1-10	2 contacts →
	Exact match “EMPOWER INFRASTRUCTURE LLC is registered as CBE, SBE, and DBE for Washington DC, DDOT, Virginia, VDOT, and WMATA.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
19	Allied Companies	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	11-50	1 contacts →
	Exact match “Professional services firm providing civil and environmental engineering as well as Program Management & Construction Management to government and private clients.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
20	Global, Inc. USA	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	1-10	1 contacts →
	Exact match “Global, Inc.” Recorded in the RevenueBase company graph · Sep 16, 2026 · View company records in RevenueBase
21	Atlantic Geopros	Exact match	Washington, DC, United StatesHQ recorded Sep 16, 2026	1-10	1 contacts →
	Exact match “Industrial Land Acquisition & Management” Recorded in the RevenueBase company graph · Sep 16, 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 “environmental engineering firms”. 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 21 of 32 environmental engineering firms based in Washington, United States

See the full list, filter by size, metro and specialty, and access 199 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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

As of Sep 16, 2026

52.0%Verified-email coverage

12.0Average contacts per company

11-50Median size (employees)

Sep 16, 2026Page data refreshed

Companies by employee count

1-10

11-50

51-200

201-500

Email recency for this list is measured across the whole United States list rather than for Washington, so it is reported there. Company counts and contact totals on this page are exact for Washington, over 32 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 Washington, United States whose business descriptions match “environmental engineering firms” 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 199 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 September 16, 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.

Environmental engineering firms by metro in the United States

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 “environmental engineering firms”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many environmental engineering firms are there based in Washington, United States?

RevenueBase identified 32 company matches for environmental engineering firms associated with Washington, United States as of September 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?

Delon Hampton & Associates, Chartered tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city in the United States has the most environmental engineering firms?

Houston leads the United States with 138 company records, followed by New York (101) and Austin (73). Washington has 32.

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 199 professional contacts with verified work emails tracked across these 32 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 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 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.