Company lists · Data refreshed September 2026
Top 25 Stormwater compliance consulting firms based in the United States
RevenueBase identified 1,778 stormwater compliance consulting firms headquartered in the United States as of September 2026 and tracks 53,466 professional contacts across them, including 24,486 with verified work emails and 22,327 with mobile numbers. Houston is the largest hub.
This list covers stormwater compliance consulting firms headquartered in the 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 6, 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.
The 25 largest stormwater compliance consulting firms based in the United States
Ranked by team size| # | Company | RevenueBase Smart Search | Contacts | ||
|---|---|---|---|---|---|
| 1 | Indirect evidence | 12,999 contacts → | |||
“Tetra Tech is the leader in water, environment and sustainable infrastructure, providing high-end technical and engineering services for projects worldwide.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 2 | Indirect evidence | 2,473 contacts → | |||
“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: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 3 | Partial evidence | 2,145 contacts → | |||
“Civil & Environmental Consultants, Inc.(CEC) provides comprehensive market-oriented consulting services that advance the strategic business objectives of its clients.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 4 | Indirect evidence | 2,100 contacts → | |||
“As Hazen marks 75 years, we celebrate a legacy of absolute commitment to our clients while delivering the best technical work available anywhere.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 5 | Partial evidence | 1,496 contacts → | |||
“Freese and Nichols is a professional planning, consulting and engineering firm serving clients across the United States.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 6 | Indirect evidence | 1,137 contacts → | |||
“Who is Apex?” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 7 | Partial evidence | 961 contacts → | |||
“Trinity Consultants is a global team of experts helping organizations solve complex challenges in environmental compliance, ecological protection, infrastructure performance, and…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 8 | Indirect evidence | 865 contacts → | |||
“ATC Group Services LLC is now Atlas.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 9 | Partial evidence | 732 contacts → | |||
“ESA is a 100% employee-owned environmental consulting firm.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 10 | Partial evidence | 577 contacts → | |||
“Headquartered in Laramie, Wyoming, Trihydro provides environmental consulting, engineering and surveying, air quality and process management, information technology, and water and…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 11 | Partial evidence | 479 contacts → | |||
“Headquartered in Seattle, Washington, Anchor QEA is a nationally recognized environmental science and engineering consulting firm specializing in aquatic, shoreline, and water…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 12 | Partial evidence | 479 contacts → | |||
“Rincon Consultants is a multi-disciplinary environmental sciences, planning, and engineering consulting firm that provides quality professional services to government and industry.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 13 | Indirect evidence | 447 contacts → | |||
“We are Groundwater & Environmental Services, Inc, better known as GES.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 14 | Partial evidence | 433 contacts → | |||
“Founded 40 years ago, Roux is recognized for being a highly effective, client-focused environmental consulting and management firm.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 15 | Indirect evidence | 371 contacts → | |||
“HRG assists with the planning, design, and management of community infrastructure.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 16 | Partial evidence | 315 contacts → | |||
“Tata & Howard is a 100% employee owned, award-winning, specialized consulting engineering firm dedicated to providing superior client service coupled with delivering…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 17 | Partial evidence | 268 contacts → | |||
“For more than 30 years, WSSI has been the trusted partner in environmental, regulatory, cultural resources, and water resources engineering consulting.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 18 | Indirect evidence | 250 contacts → | |||
“Celebrating years of innovation and design, HRC provides professional engineering, environmental engineering, and architectural services to municipal, industrial and private…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 19 | Indirect evidence | 238 contacts → | |||
“Environmental Works, Inc.(EWI) offers truly comprehensive environmental solutions for a variety of industries, businesses, and municipalities.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 20 | Partial evidence | 199 contacts → | |||
“HELIX Environmental Planning, Inc.(HELIX) is an employee-owned, environmental consulting firm established in 1991 and with offices in San Diego, Los Angeles, Orange, Riverside…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 21 | Indirect evidence | 189 contacts → | |||
Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 22 | Partial evidence | 184 contacts → | |||
“Landau Associates is an employee-owned firm that provides environmental consulting and risk management for clients across many disciplines including air, noise, water, permitting…” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 23 | Partial evidence | 176 contacts → | |||
“Herrera Environmental Consultants is a leading engineering and scientific consulting firm focused on restoration, water, and sustainable development.” Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 24 | Indirect evidence | 166 contacts → | |||
Source: company website · checked Sep 6, 2026Thanks. The Data Team will review it. | |||||
| 25 | Indirect evidence | 165 contacts → | |||
“WestLand Engineering & Environmental Services, has been a leading engineering and environmental services firm since 1997.” Source: company website · checked Sep 6, 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: stormwater compliance 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 stormwater compliance consulting firms.
- Partial evidence
- Its own public description names part of stormwater compliance consulting firms, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name stormwater compliance 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 1,778 stormwater compliance consulting firms based in the United States
See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 24,486 reachable decision-makers.
Free signup · no credit card
Stormwater compliance consulting firms based in the United States at a glance
As of Sep 6, 2026Companies by employee count
Freshness & accuracy
How recently the business emails on this list were verified
Email last verified
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 stormwater compliance 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.
- What qualifies
- Companies headquartered in the United States whose own description of what they do matches “stormwater compliance 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 stormwater compliance 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 stormwater compliance consulting firms, and records with no verified work email. Companies headquartered outside United States 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, 24,486 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 6, 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.
Stormwater compliance consulting firms by metro
- Stormwater compliance consulting firms in Houston40
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 stormwater compliance 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 stormwater compliance consulting firms are there based in the United States?
RevenueBase identified 1,778 stormwater compliance consulting firms headquartered in the 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?
Tetra Tech, headquartered in Pasadena, tops this list with the largest team on record.
Which city has the most stormwater compliance consulting firms?
Houston leads with 40 headquartered companies, followed by Seattle (22) and San Diego (20).
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 24,486 verified decision-maker contacts tracked across these 1,778 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 6, 2026.
Ready to reach these companies? Verified emails and direct dials for all 1,778 stormwater compliance consulting firms based in the United States. Start with a free account, no credit card.
Download this list →Related lists
Stormwater compliance consulting firms by geography
- Stormwater compliance consulting firms based in Brazil
- Stormwater compliance consulting firms based in Canada
- Stormwater compliance consulting firms based in France
- Stormwater compliance consulting firms based in Australia
- Stormwater compliance consulting firms based in Germany
- Stormwater compliance consulting firms based in the United Kingdom
- Stormwater compliance consulting firms based in Italy
Browse the directory
Browse: Companies home · All United States lists · All Stormwater compliance consulting firms lists · New lists
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.
More company lists
- All company lists
- Lists by location
- Lists A-Z
- New lists
- Stormwater compliance consulting firms based in Brazil
- Stormwater compliance consulting firms based in Canada
- Stormwater compliance consulting firms based in France
- Stormwater compliance consulting firms based in Australia
- Stormwater compliance consulting firms based in Germany
- Stormwater compliance consulting firms based in the United Kingdom