Top 30 Water & Wastewater Engineering Companies 2027

This report forms part of The Economy Rankings’ Transportation & Heavy Engineering portfolio. It compares water & wastewater engineering companies through the relevant operating businesses, their industrial specialization and their documented market roles.

Water and wastewater engineering combines treatment technology with the realities of an operating utility or industrial site. Influent quality, required discharge conditions, energy use and maintenance resources shape the appropriate solution.

A treatment process should be selected against a defined water quality and operating duty. Laboratory capability or a technology catalogue cannot alone establish the performance of a full installed system.

The 2027 edition is an advance editorial comparison informed by material available through 23 October 2026. It considers companies executing design-build or integrated engineering of water/wastewater treatment and water infrastructure. The focus is on treatment engineering, project integration and operating support, interpreted within the boundaries of this particular market.

Thirty entries are presented in three tiers. Tier I identifies five leading businesses in an explicit editorial order; Tier II and Tier III contain ten and fifteen entries respectively and are presented alphabetically. The comparison concerns the named industrial activity, rather than every product, subsidiary or service associated with a corporate group.

Market Overview

Heavy engineering combines technical design with the capacity to manufacture or execute a complex physical system. Order books, product announcements and project awards describe activity, but they do not by themselves establish a completed industrial outcome. The relevant comparison follows the operating business and its actual contribution to a vehicle, vessel, plant or infrastructure project.

Within water & wastewater engineering companies, the central issue is treatment engineering. A treatment process should be selected against a defined water quality and operating duty. Laboratory capability or a technology catalogue cannot alone establish the performance of a full installed system. This makes the relationship between the offered capability and the customer’s operating conditions a useful way to distinguish competitors.

The market also contains different degrees of specialization. Some businesses address a narrow industrial task; others combine it with several adjacent activities. Neither breadth nor focus is sufficient on its own. The relevant distinction is whether the assessed business has a substantive role in companies executing design-build or integrated engineering of water/wastewater treatment and water infrastructure.

Looking toward the 2027 planning period, water reuse and industrial effluent treatment provide useful areas for comparison. These are purchasing and operating priorities, not claims that future outcomes have already occurred. A meaningful assessment keeps project integration and operating support connected to the same defined market.

Industry Trend — 2027

The following themes frame the sector’s 2027 planning environment. They describe industrial questions arising from the current product and service landscape, rather than a statistical forecast or a claim of completed 2027 performance.

2027 market development	Current evidence and direction	Implication for the sector
Water reuse	The choice is increasingly connected with the complete operating workflow.	Compare treatment engineering with the intended application.
Industrial effluent treatment	Specialist capabilities need to remain compatible with the wider industrial process.	Consider project integration alongside practical implementation requirements.
Energy-aware operation	A documented offering must be interpreted within its actual product or service scope.	Distinguish the supplied capability from an assumed customer outcome.
Modular treatment systems	Support over the operating life remains part of the industrial proposition.	Connect operating support with the responsibilities of the assessed operating business.

For this market, the common thread is the connection between treatment engineering and a workable industrial application. The comparison therefore treats the operating business and its defined contribution as more informative than a general claim to scale, innovation or market leadership.

Methodology — Core Eligibility Criteria

This series uses a qualitative editorial comparison of publicly described industrial activities. The evaluated unit is OEM, system supplier or contractor (defined per series). The same identity and market boundaries apply throughout the three tiers.

• Eligible population: Companies executing design-build or integrated engineering of water/wastewater treatment and water infrastructure
• Excluded from this comparison: Municipal water utility operators without qualifying engineering business; chemicals suppliers only
• The entry must identify a substantive operating manufacturer, producer, contractor or service business relevant to the named market.
• A parent company and its controlled business are not counted twice for the same assessed activity. Corporate and historical names are interpreted through the operating scope.
• Public company, product, project and service information is considered according to its relevance. A marketing slogan, customer logo or certificate image alone does not establish a measured outcome.
• Selection, tier placement and the order of the leading five are independent of licensing, advertising, sponsorship and the prospect of purchasing recognition materials.

Methodology — Ranking Factors

• Documented engineering and execution scope — 30%: The systems manufactured or project responsibilities undertaken in the relevant market. In this series, this is interpreted through treatment engineering.
• Product and project quality requirements — 25%: The qualification, safety and quality demands associated with the defined business. In this series, this is interpreted through project integration.
• Technical specialization and integration — 20%: The engineering role and the ability to connect components or work packages into a useful system. In this series, this is interpreted through operating support.
• Delivery architecture and lifecycle support — 15%: The production, project and support arrangements surrounding the supplied system. In this series, this is interpreted through treatment engineering.
• Evidence clarity and responsible operations — 10%: Traceable business identity and a disciplined distinction between public facts and unsupported performance claims. In this series, this is interpreted through project integration.

The percentages specify editorial emphasis; they are not reported company scores or the results of common laboratory testing. Tier membership and the leading-five order reflect a qualitative judgment of the documented industrial proposition. Product-specific approvals, specifications and customer outcomes remain limited to the context in which they are established.

Company Profiles and Further Reference

The names below link to company-reference locations in The Economy Wiki. Wiki coverage is maintained separately from this annual edition; individual pages may be added or updated as part of that reference work.

The profiles identify the business being compared and explain its relevance to this particular industrial market. Historical origins refer to the stated business or corporate formation, while a current operating name may be more recent. A group headquarters is distinguished from a factory or regional service location where the available identity record permits that distinction.

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Tier I — Leading Water & Wastewater Engineering Companies

1. Veolia

• Assessed business: Veolia
• Headquarters / operating-company base: Aubervilliers, France
• Business origins / formation: 1853

Veolia combines water-treatment technologies, project capabilities and operating services, connecting treatment equipment with a wider utility and industrial-water business. The comparison follows the operating manufacturer, system supplier or execution contractor defined for this series and the contribution of that business to the market described here.

The industrial significance of this offering becomes clearer when considering the defined engineering responsibility. A buyer is selecting a contribution to an operating system, with a defined industrial task and operating environment. For Veolia, the relevant comparison connects its the relevant operating activities described in this series with the application requirements set out in this series.

The assessment places this business within a comparison that values treatment engineering, project integration and operating support. Its particular operating focus provides the reason for inclusion; the tier should be interpreted through this series rather than transferred to unrelated products or services. For Veolia, this interpretation is tied specifically to the relevant operating activities described in this series.

2. SUEZ

• Assessed business: SUEZ

SUEZ supplies water and wastewater technologies and services, with industrial and municipal treatment activities forming the relevant operating scope. The comparison follows the operating manufacturer, system supplier or execution contractor defined for this series and the contribution of that business to the market described here.

For SUEZ, the useful comparison is the relationship between the system or project boundary and the treatment of modifications after delivery. Its the relevant operating activities described in this series establish the business being considered. The editorial assessment gives attention to how that specialization fits the market, while keeping product-specific or contract-specific results separate from a group-level description.

Its position recognizes the relevance of that industrial proposition to project integration and operating support. The practical question for a purchaser remains whether the named business fits the required application, operating environment and level of support. For SUEZ, this interpretation is tied specifically to the relevant operating activities described in this series.

3. Xylem

• Assessed business: Xylem

Xylem combines water technologies with engineering and integration capabilities, including treatment-system activities within its broader water-equipment business. The comparison follows the operating manufacturer, system supplier or execution contractor defined for this series and the contribution of that business to the market described here.

The distinctive feature for this comparison is the combination of water transport, treatment and measurement technologies with an identifiable industrial operating business. That makes the manufacturing contribution rather than a contract headline a more useful reference point than general corporate scale. Xylem is considered within that boundary, so activities outside the named market do not determine its standing.

This operating focus gives the company a specific role in the sector’s competitive landscape. The comparison considers project integration alongside operating support, allowing specialist capabilities to remain visible without treating a broad corporate portfolio as evidence of superiority in every application. For Xylem, this interpretation is tied specifically to water transport, treatment and measurement technologies.

4. Metito

• Assessed business: Metito

Metito develops and delivers water and wastewater systems, connecting treatment engineering with project and operating requirements. The comparison follows the operating manufacturer, system supplier or execution contractor defined for this series and the contribution of that business to the market described here.

This business illustrates why the relationship between design and physical execution matters in industrial selection. The offer centers on the relevant operating activities described in this series, and the assessment follows that contribution rather than assuming that every business line is equally relevant. For a customer, the connection between project experience and the current business provides a practical way to interpret the company’s place in the comparison.

That specialization is the central reason to consider the company in this field. Its tier reflects an editorial comparison within the stated market, with operating support considered alongside the substantive industrial offering. A purchasing decision still needs to connect the particular requirement with the relevant operating business. For Metito, this interpretation is tied specifically to the relevant operating activities described in this series.

5. VA TECH WABAG

• Assessed business: VA TECH WABAG
• Headquarters / operating-company base: Chennai, Tamil Nadu, India

VA TECH WABAG concentrates on water and wastewater treatment engineering, with plant delivery and related operating services central to its business. The comparison follows the operating manufacturer, system supplier or execution contractor defined for this series and the contribution of that business to the market described here.

VA TECH WABAG represents a defined route into this market through the relevant operating activities described in this series. Its inclusion is therefore best read alongside the interfaces with other suppliers and contractors, rather than as a universal recommendation across all industrial purchases. The business provides a useful reference for comparing operating specialization with the broader requirements of the sector.

This operating focus gives the company a specific role in the sector’s competitive landscape. The comparison considers project integration alongside operating support, allowing specialist capabilities to remain visible without treating a broad corporate portfolio as evidence of superiority in every application. For VA TECH WABAG, this interpretation is tied specifically to the relevant operating activities described in this series.

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Tier II — Established Water & Wastewater Engineering Companies

(Alphabetical order)

Acciona

• Assessed business: Acciona
• Headquarters / operating-company base: Alcobendas, Spain
• Business origins / formation: 1997 (1931 Entrecanales y Távora)

Acciona supplies civil-engineering, infrastructure and water-project delivery. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

The industrial significance of this offering becomes clearer when considering the qualification requirements of the operating application. A buyer is selecting a contribution to an operating system, with a defined industrial task and operating environment. For Acciona, the relevant comparison connects its civil-engineering, infrastructure and water-project delivery with the application requirements set out in this series.

This operating focus gives the company a specific role in the sector’s competitive landscape. The comparison considers project integration alongside operating support, allowing specialist capabilities to remain visible without treating a broad corporate portfolio as evidence of superiority in every application. For Acciona, this interpretation is tied specifically to civil-engineering, infrastructure and water-project delivery.

AECOM

• Assessed business: AECOM
• Headquarters / operating-company base: Dallas, Texas, United States
• Business origins / formation: 1990

AECOM supplies water and civil-infrastructure engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

For AECOM, the useful comparison is the relationship between the fit between the offered system and its operating environment and the evidence supporting an operating production business. Its water and civil-infrastructure engineering establish the business being considered. The editorial assessment gives attention to how that specialization fits the market, while keeping product-specific or contract-specific results separate from a group-level description.

The assessment places this business within a comparison that values treatment engineering, project integration and operating support. Its particular operating focus provides the reason for inclusion; the tier should be interpreted through this series rather than transferred to unrelated products or services. For AECOM, this interpretation is tied specifically to water and civil-infrastructure engineering.

Aquatech

• Assessed business: Aquatech

Aquatech supplies industrial water treatment and reuse technologies. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

The distinctive feature for this comparison is the combination of industrial water treatment and reuse technologies with an identifiable industrial operating business. That makes the support arrangements over a long asset life a more useful reference point than general corporate scale. Aquatech is considered within that boundary, so activities outside the named market do not determine its standing.

Its position recognizes the relevance of that industrial proposition to project integration and operating support. The practical question for a purchaser remains whether the named business fits the required application, operating environment and level of support. For Aquatech, this interpretation is tied specifically to industrial water treatment and reuse technologies.

Arcadis

• Assessed business: Arcadis
• Headquarters / operating-company base: Zuidas, Amsterdam, Netherlands
• Business origins / formation: 1888

Arcadis supplies water and industrial infrastructure engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

The distinctive feature for this comparison is the combination of water and industrial infrastructure engineering with an identifiable industrial operating business. That makes the treatment of modifications after delivery a more useful reference point than general corporate scale. Arcadis is considered within that boundary, so activities outside the named market do not determine its standing.

That specialization is the central reason to consider the company in this field. Its tier reflects an editorial comparison within the stated market, with operating support considered alongside the substantive industrial offering. A purchasing decision still needs to connect the particular requirement with the relevant operating business. For Arcadis, this interpretation is tied specifically to water and industrial infrastructure engineering.

AtkinsRéalis

• Assessed business: AtkinsRéalis
• Headquarters / operating-company base: Montreal, Quebec, Canada
• Business origins / formation: 1911

AtkinsRéalis supplies industrial and water-infrastructure engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

AtkinsRéalis represents a defined route into this market through industrial and water-infrastructure engineering. Its inclusion is therefore best read alongside the connection between project experience and the current business, rather than as a universal recommendation across all industrial purchases. The business provides a useful reference for comparing operating specialization with the broader requirements of the sector.

The assessment places this business within a comparison that values treatment engineering, project integration and operating support. Its particular operating focus provides the reason for inclusion; the tier should be interpreted through this series rather than transferred to unrelated products or services. For AtkinsRéalis, this interpretation is tied specifically to industrial and water-infrastructure engineering.

Black & Veatch

• Assessed business: Black & Veatch
• Headquarters / operating-company base: Overland Park, Kansas
• Business origins / formation: 1915

Black & Veatch supplies industrial and infrastructure engineering and construction. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

This business illustrates why the distinction between a product family and a single contract matters in industrial selection. The offer centers on industrial and infrastructure engineering and construction, and the assessment follows that contribution rather than assuming that every business line is equally relevant. For a customer, the industrial contribution of a specialist supplier provides a practical way to interpret the company’s place in the comparison.

This operating focus gives the company a specific role in the sector’s competitive landscape. The comparison considers project integration alongside operating support, allowing specialist capabilities to remain visible without treating a broad corporate portfolio as evidence of superiority in every application. For Black & Veatch, this interpretation is tied specifically to industrial and infrastructure engineering and construction.

IDE Technologies

• Assessed business: IDE Technologies
• Headquarters / operating-company base: Hamatechet Street, Hasharon Industrial Park, Kadima, Israel
• Business origins / formation: 1965

IDE Technologies supplies desalination and industrial water-treatment engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

For IDE Technologies, the useful comparison is the relationship between the resources required during commissioning and the customer’s access to technical and operating support. Its desalination and industrial water-treatment engineering establish the business being considered. The editorial assessment gives attention to how that specialization fits the market, while keeping product-specific or contract-specific results separate from a group-level description.

This operating focus gives the company a specific role in the sector’s competitive landscape. The comparison considers project integration alongside operating support, allowing specialist capabilities to remain visible without treating a broad corporate portfolio as evidence of superiority in every application. For IDE Technologies, this interpretation is tied specifically to desalination and industrial water-treatment engineering.

Jacobs

• Assessed business: Jacobs

Jacobs supplies water and infrastructure engineering services. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

Jacobs represents a defined route into this market through water and infrastructure engineering services. Its inclusion is therefore best read alongside the engineering role within a larger industrial program, rather than as a universal recommendation across all industrial purchases. The business provides a useful reference for comparing operating specialization with the broader requirements of the sector.

Its position recognizes the relevance of that industrial proposition to project integration and operating support. The practical question for a purchaser remains whether the named business fits the required application, operating environment and level of support. For Jacobs, this interpretation is tied specifically to water and infrastructure engineering services.

Stantec

• Assessed business: Stantec
• Headquarters / operating-company base: Edmonton, Alberta, Canada
• Business origins / formation: 1954

Stantec supplies water-treatment and infrastructure engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

The industrial significance of this offering becomes clearer when considering the responsibilities attached to a delivered system. A buyer is selecting a contribution to an operating system, with a defined industrial task and operating environment. For Stantec, the relevant comparison connects its water-treatment and infrastructure engineering with the application requirements set out in this series.

This operating focus gives the company a specific role in the sector’s competitive landscape. The comparison considers project integration alongside operating support, allowing specialist capabilities to remain visible without treating a broad corporate portfolio as evidence of superiority in every application. For Stantec, this interpretation is tied specifically to water-treatment and infrastructure engineering.

WSP

• Assessed business: WSP

WSP supplies water and infrastructure engineering services. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

This business illustrates why the production resources behind a repeatable offering matters in industrial selection. The offer centers on water and infrastructure engineering services, and the assessment follows that contribution rather than assuming that every business line is equally relevant. For a customer, the continuity of a long-term industrial program provides a practical way to interpret the company’s place in the comparison.

The assessment places this business within a comparison that values treatment engineering, project integration and operating support. Its particular operating focus provides the reason for inclusion; the tier should be interpreted through this series rather than transferred to unrelated products or services. For WSP, this interpretation is tied specifically to water and infrastructure engineering services.

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Tier III — Recognized Water & Wastewater Engineering Companies

(Alphabetical order)

Arup

• Assessed business: Arup
• Headquarters / operating-company base: London, United Kingdom
• Business origins / formation: 1946

Arup supplies water and civil-infrastructure engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

For Arup, the useful comparison is the relationship between the division between new construction and lifecycle service and the coordination of manufacturing and supplier activities. Its water and civil-infrastructure engineering establish the business being considered. The editorial assessment gives attention to how that specialization fits the market, while keeping product-specific or contract-specific results separate from a group-level description.

Its position recognizes the relevance of that industrial proposition to project integration and operating support. The practical question for a purchaser remains whether the named business fits the required application, operating environment and level of support. For Arup, this interpretation is tied specifically to water and civil-infrastructure engineering.

Brown and Caldwell

• Assessed business: Brown and Caldwell

Brown and Caldwell supplies water and environmental engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

The distinctive feature for this comparison is the combination of water and environmental engineering with an identifiable industrial operating business. That makes the evidence supporting an operating production business a more useful reference point than general corporate scale. Brown and Caldwell is considered within that boundary, so activities outside the named market do not determine its standing.

Its position recognizes the relevance of that industrial proposition to project integration and operating support. The practical question for a purchaser remains whether the named business fits the required application, operating environment and level of support. For Brown and Caldwell, this interpretation is tied specifically to water and environmental engineering.

Burns & McDonnell

• Assessed business: Burns & McDonnell
• Headquarters / operating-company base: Kansas City, Missouri, United States
• Business origins / formation: 1898

Burns & McDonnell supplies engineering and construction for industrial facilities. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

Burns & McDonnell represents a defined route into this market through engineering and construction for industrial facilities. Its inclusion is therefore best read alongside the continuity of a long-term industrial program, rather than as a universal recommendation across all industrial purchases. The business provides a useful reference for comparing operating specialization with the broader requirements of the sector.

The assessment places this business within a comparison that values treatment engineering, project integration and operating support. Its particular operating focus provides the reason for inclusion; the tier should be interpreted through this series rather than transferred to unrelated products or services. For Burns & McDonnell, this interpretation is tied specifically to engineering and construction for industrial facilities.

CDM Smith

• Assessed business: CDM Smith
• Headquarters / operating-company base: 75 State Street, Boston, Massachusetts, US
• Business origins / formation: 1947

CDM Smith supplies water and industrial infrastructure engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

This business illustrates why the responsibility for interfaces during project handover matters in industrial selection. The offer centers on water and industrial infrastructure engineering, and the assessment follows that contribution rather than assuming that every business line is equally relevant. For a customer, the interfaces with other suppliers and contractors provides a practical way to interpret the company’s place in the comparison.

This operating focus gives the company a specific role in the sector’s competitive landscape. The comparison considers project integration alongside operating support, allowing specialist capabilities to remain visible without treating a broad corporate portfolio as evidence of superiority in every application. For CDM Smith, this interpretation is tied specifically to water and industrial infrastructure engineering.

GHD

• Assessed business: GHD

GHD supplies water and infrastructure engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

The industrial significance of this offering becomes clearer when considering the conditions under which different product classes can be compared. A buyer is selecting a contribution to an operating system, with a defined industrial task and operating environment. For GHD, the relevant comparison connects its water and infrastructure engineering with the application requirements set out in this series.

The company’s place in the ranking reflects the fit between this operating scope and the series’ industrial definition. For customers examining project integration, it offers a concrete business to compare on specification, execution requirements and the support surrounding the selected product or service. For GHD, this interpretation is tied specifically to water and infrastructure engineering.

H2O Innovation

• Assessed business: H2O Innovation

H2O Innovation supplies water-treatment systems and related services. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

The distinctive feature for this comparison is the combination of water-treatment systems and related services with an identifiable industrial operating business. That makes the coordination of manufacturing and supplier activities a more useful reference point than general corporate scale. H2O Innovation is considered within that boundary, so activities outside the named market do not determine its standing.

The assessment places this business within a comparison that values treatment engineering, project integration and operating support. Its particular operating focus provides the reason for inclusion; the tier should be interpreted through this series rather than transferred to unrelated products or services. For H2O Innovation, this interpretation is tied specifically to water-treatment systems and related services.

Hazen and Sawyer

• Assessed business: Hazen and Sawyer

Hazen and Sawyer supplies water and wastewater engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

For Hazen and Sawyer, the useful comparison is the relationship between the distinction between engineering advice and execution and the manufacturing contribution rather than a contract headline. Its water and wastewater engineering establish the business being considered. The editorial assessment gives attention to how that specialization fits the market, while keeping product-specific or contract-specific results separate from a group-level description.

This operating focus gives the company a specific role in the sector’s competitive landscape. The comparison considers project integration alongside operating support, allowing specialist capabilities to remain visible without treating a broad corporate portfolio as evidence of superiority in every application. For Hazen and Sawyer, this interpretation is tied specifically to water and wastewater engineering.

Kurita Water Industries

• Assessed business: Kurita Water Industries
• Headquarters / operating-company base: Nakano-ku, Tokyo 164-0001, Japan
• Business origins / formation: 1949

Kurita Water Industries supplies water-treatment chemistry and engineering systems. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

Kurita Water Industries represents a defined route into this market through water-treatment chemistry and engineering systems. Its inclusion is therefore best read alongside the practical boundary between corporate scale and engineering fit, rather than as a universal recommendation across all industrial purchases. The business provides a useful reference for comparing operating specialization with the broader requirements of the sector.

This operating focus gives the company a specific role in the sector’s competitive landscape. The comparison considers project integration alongside operating support, allowing specialist capabilities to remain visible without treating a broad corporate portfolio as evidence of superiority in every application. For Kurita Water Industries, this interpretation is tied specifically to water-treatment chemistry and engineering systems.

Larsen & Toubro

• Assessed business: Larsen & Toubro
• Headquarters / operating-company base: L&T House, Ballard Estate, Mumbai, Maharashtra, India
• Business origins / formation: 1946

Larsen & Toubro supplies industrial construction, engineering and infrastructure delivery. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

The industrial significance of this offering becomes clearer when considering the relevance of an organization’s wider capabilities to this series. A buyer is selecting a contribution to an operating system, with a defined industrial task and operating environment. For Larsen & Toubro, the relevant comparison connects its industrial construction, engineering and infrastructure delivery with the application requirements set out in this series.

Its position recognizes the relevance of that industrial proposition to project integration and operating support. The practical question for a purchaser remains whether the named business fits the required application, operating environment and level of support. For Larsen & Toubro, this interpretation is tied specifically to industrial construction, engineering and infrastructure delivery.

Mott MacDonald

• Assessed business: Mott MacDonald
• Headquarters / operating-company base: City of London, England
• Business origins / formation: 1989

Mott MacDonald supplies water and infrastructure engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

The industrial significance of this offering becomes clearer when considering the boundaries of any approval or certification claim. A buyer is selecting a contribution to an operating system, with a defined industrial task and operating environment. For Mott MacDonald, the relevant comparison connects its water and infrastructure engineering with the application requirements set out in this series.

That specialization is the central reason to consider the company in this field. Its tier reflects an editorial comparison within the stated market, with operating support considered alongside the substantive industrial offering. A purchasing decision still needs to connect the particular requirement with the relevant operating business. For Mott MacDonald, this interpretation is tied specifically to water and infrastructure engineering.

Nijhuis Saur Industries

• Assessed business: Nijhuis Saur Industries

Nijhuis Saur Industries supplies industrial water-treatment and reuse systems. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

For Nijhuis Saur Industries, the useful comparison is the relationship between the relationship between standard platforms and custom requirements and the support arrangements over a long asset life. Its industrial water-treatment and reuse systems establish the business being considered. The editorial assessment gives attention to how that specialization fits the market, while keeping product-specific or contract-specific results separate from a group-level description.

That specialization is the central reason to consider the company in this field. Its tier reflects an editorial comparison within the stated market, with operating support considered alongside the substantive industrial offering. A purchasing decision still needs to connect the particular requirement with the relevant operating business. For Nijhuis Saur Industries, this interpretation is tied specifically to industrial water-treatment and reuse systems.

Organo

• Assessed business: Organo

Organo supplies industrial water-treatment equipment and systems. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

This business illustrates why the resources available for maintaining the delivered asset matters in industrial selection. The offer centers on industrial water-treatment equipment and systems, and the assessment follows that contribution rather than assuming that every business line is equally relevant. For a customer, the engineering role within a larger industrial program provides a practical way to interpret the company’s place in the comparison.

That specialization is the central reason to consider the company in this field. Its tier reflects an editorial comparison within the stated market, with operating support considered alongside the substantive industrial offering. A purchasing decision still needs to connect the particular requirement with the relevant operating business. For Organo, this interpretation is tied specifically to industrial water-treatment equipment and systems.

Ramboll

• Assessed business: Ramboll
• Headquarters / operating-company base: Copenhagen, Denmark
• Business origins / formation: 1945

Ramboll supplies water and environmental engineering. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

The distinctive feature for this comparison is the combination of water and environmental engineering with an identifiable industrial operating business. That makes the customer’s access to technical and operating support a more useful reference point than general corporate scale. Ramboll is considered within that boundary, so activities outside the named market do not determine its standing.

That specialization is the central reason to consider the company in this field. Its tier reflects an editorial comparison within the stated market, with operating support considered alongside the substantive industrial offering. A purchasing decision still needs to connect the particular requirement with the relevant operating business. For Ramboll, this interpretation is tied specifically to water and environmental engineering.

Sweco

• Assessed business: Sweco
• Headquarters / operating-company base: Kungsholmen, Stockholm, Sweden
• Business origins / formation: 1997

Sweco supplies water and industrial engineering services. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

This business illustrates why the way components are integrated into the complete asset matters in industrial selection. The offer centers on water and industrial engineering services, and the assessment follows that contribution rather than assuming that every business line is equally relevant. For a customer, the practical boundary between corporate scale and engineering fit provides a practical way to interpret the company’s place in the comparison.

The company’s place in the ranking reflects the fit between this operating scope and the series’ industrial definition. For customers examining project integration, it offers a concrete business to compare on specification, execution requirements and the support surrounding the selected product or service. For Sweco, this interpretation is tied specifically to water and industrial engineering services.

Tetra Tech

• Assessed business: Tetra Tech
• Headquarters / operating-company base: Pasadena, California, United States
• Business origins / formation: 1966

Tetra Tech supplies water and environmental engineering services. Its relevance to this ranking comes from that defined operating scope. The assessment concerns the operating manufacturer, system supplier or execution contractor defined for this series, with emphasis on treatment engineering rather than the reputation of unrelated group activities.

Tetra Tech represents a defined route into this market through water and environmental engineering services. Its inclusion is therefore best read alongside the industrial contribution of a specialist supplier, rather than as a universal recommendation across all industrial purchases. The business provides a useful reference for comparing operating specialization with the broader requirements of the sector.

That specialization is the central reason to consider the company in this field. Its tier reflects an editorial comparison within the stated market, with operating support considered alongside the substantive industrial offering. A purchasing decision still needs to connect the particular requirement with the relevant operating business. For Tetra Tech, this interpretation is tied specifically to water and environmental engineering services.

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Remarks

This edition evaluates water & wastewater engineering companies within the operating definition above. Water and wastewater engineering combines treatment technology with the realities of an operating utility or industrial site. Influent quality, required discharge conditions, energy use and maintenance resources shape the appropriate solution. The comparison should therefore be read through treatment engineering, project integration and operating support, rather than as a judgment about every activity of an included organization.

The ranking is an editorial comparison based on information available through 23 October 2026. It is not a product certification, procurement guarantee or independently conducted performance test. The three tiers describe the relative editorial assessment within this series; alphabetical placement within Tier II or Tier III is not an individual numerical rank.

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Recognition

Inclusion in the Top 30 Water & Wastewater Engineering Companies 2027 ranking is an editorial determination of The Economy Rankings and does not require licensing, advertising, sponsorship, or other commercial participation.

Ranked organizations may factually refer to their inclusion in the ranking in their own communications. When describing the result, entities should accurately reflect the tier structure and methodology used in the published ranking.

How the ranking should be interpreted

• Tier I represents the Top 5 entities, and the published order within Tier I reflects the ranking order.
• Tier II represents entities ranked within the Top 15, following Tier I. Entities within Tier II are displayed alphabetically; their displayed order should therefore not be interpreted as an individual numerical ranking.
• Tier III represents entities ranked within the Top 30, following Tiers I and II. Entities within Tier III are also displayed alphabetically, and their displayed order should not be interpreted as an individual numerical ranking.
• An entity's tier, rather than its alphabetical position within Tier II or Tier III, should therefore be used when describing its standing.

Referencing the ranking

Depending on the entity's published tier, appropriate factual descriptions may include:

• Tier I: “Ranked Tier I” or “Ranked among the Top 5”
• Tier II: “Ranked Tier II” or “Ranked among the Top 15”
• Tier III: “Ranked Tier III” or “Ranked among the Top 30”

Entities should not describe an alphabetical position within Tier II or Tier III as a specific numerical rank.

Use of The Economy Rankings recognition materials

Editorial inclusion in a ranking does NOT by itself grant permission to use The Economy Rankings badges, seals, logos, official recognition graphics, licensed quotations, or other proprietary recognition materials.

Organizations wishing to use official The Economy Rankings recognition materials in corporate websites, marketing materials, investor communications, client presentations, social media, press releases, or other external communications should refer to the applicable licensing terms and usage policies:

• The Economy Rankings License Structure — available licence levels and permitted recognition uses
  The Economy Rankings License Structure | The Economy Rankings
• The Economy Rankings License Policy — licensing conditions governing use of The Economy Rankings recognition, marks, and related materials
  The Economy Rankings License Policy | The Economy Rankings
• Recognition Use Guide — guidance on permitted wording, presentation, attribution, and use of ranking recognition
  Recognition Use Guide | The Economy Rankings

Purchasing or holding a recognition-materials licence does not confer inclusion or a higher tier.

Recognized organizations may reference the designation in:

• corporate websites
• investor communications
• marketing materials
• client presentations

Licensing inquiries:
[email protected]