**Exhibit 8.1**

 

**SUBSIDIARIESOF ARCADIS N.V.**

 

**CONSOLIDATEDCOMPANIES (as of December 31, 2006)**

 
| **Entity**                                           | ** ** | **Jurisdiction** |
|------------------------------------------------------|------------|------------------|
| ARCADIS US, Inc.                                     |       | Delaware         |
| ARCADIS Nederland B.V.                               |       | The Netherlands  |
| ARCADIS Europe B.V.                                  |       | The Netherlands  |
| ARCADIS USA B.V.                                     |       | The Netherlands  |
| ARCADIS Latin America B.V.                           |       | The Netherlands  |
| ARCADIS International B.V.                           |       | The Netherlands  |
| PRC B.V.                                             |       | The Netherlands  |
| ARCADIS Asia B.V.                                    |       | The Netherlands  |
| AYH plc Holding                                      |       | United Kingdom   |
| ARCADIS North America                                |       | Colorado         |
| ARCADIS Corporate Services, Inc.                     |       | Colorado         |
| ARCADIS G&M of Michigan, LLC                     |       | Michigan         |
| Reese, Macon and Associates, Inc.                    |       | Florida          |
| ARCADIS G&M of Ohio, Inc.                        |       | Ohio             |
| Lawson, Noble & Webb, Inc.                       |       | Florida          |
| ARCADIS Peru Holdings, LLC                           |       | Colorado         |
| ARCADIS Development, LLC                             |       | Colorado         |
| ARCADIS Greystone, Inc.                              |       | Colorado         |
| ARCADIS of New York, Inc.                            |       | New York         |
| PinnacleOne, Inc.                                    |       | Arizona          |
| ARCADIS-ENERGY Y Associados S.A.                     |       | Peru             |
|  AGM de Mexico  Associates, S. DE R.L. DE C.V.  |       | Mexico           |
| ARCADIS G&M of Ohio A&E, LLC                 |       | Ohio             |
| Construction Dynamics Group, Inc.                    |       | Maryland         |
| Lewis and Zimmerman Associates, Inc.                 |       | Maryland         |
| ARCADIS G&M of Michigan, LLC                     |       | Michigan         |
| CDG International, Ltd                               |       | United Kingdom   |
| ARCADIS G&M del Peru, SAC                        |       | Peru             |
| Greystone Environmental Consultants, Inc. Arizona    |       | Colorado         |
| Greystone Environmental Consultants, Inc. California |       | Colorado         |
| Greystone Environmental Consultants, Inc. Colorado   |       | Colorado         |
| Greystone Environmental Consultants, Inc. Wyoming    |       | Colorado         |
| Greystone Canada, Inc.                               |       | Canada           |
| BBL Environmental Services, Inc.                     |       | Florida          |
| Triangle Economic Research, LLC                      |       | North Carolina   |
| Glacier Creek Properties Companies                   |       | New York         |
| Cranbury Properties Company                          |       | New York         |
| BBL Servicios Ambientales de Nicaragua S.A.          |       | Nicaragua        |
| BBL Caribe Engineering P.S.C.                        |       | Puerto Rico      |
| ARCADIS Regio B.V.                                   |       | The Netherlands  |
| ARCADIS PlanRealisatie B.V.                          |       | The Netherlands  |
| ARCADIS Geo- en Vastgoedinformatie B.V.              |       | The Netherlands  |
| B.V. Boreon                                          |       | The Netherlands  |
| Onroerend Goed Balkenweg B.V.                        |       | The Netherlands  |
| ARCADIS Infra B.V.                                   |       | The Netherlands  |
| ARCADIS Support B.V.                                 |       | The Netherlands  |
| ARCADIS Euroconsult B.V.                             |       | The Netherlands  |
| ARCADIS Bouw en Vastgoed B.V.                        |       | The Netherlands  |
| ARCADIS FM Beheer B.V.                               |       | The Netherlands  |
| ARCADIS Ruimte en Milieu B.V.                        |       | The Netherlands  |
| ARCADIS Insurance Management B.V.                    |       | The Netherlands  |
| ARCADIS Projecten B.V.                               |       | The Netherlands  |

 

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| Stedebouwkundig Adviesbureau Witpaard-Partners B.V.        |   | The Netherlands |
|------------------------------------------------------------|--------|-----------------|
| Stroomdal I                                                |   | The Netherlands |
| Serasea B.V.                                               |   | The Netherlands |
| Heidemij Realisatie 3 B.V.                                 |   | The Netherlands |
| Copijn Utrecht Holding B.V.                                |   | The Netherlands |
| Heidemij Realisatie Deutschland GmbH                       |   | Germany         |
| Glastuinverplaatsing Leidsche Rijn B.V.                    |   | The Netherlands |
| Ontwikkelings Maatschappij Floris V CV                     |   | The Netherlands |
| Bio Science Park I B.V.                                    |   | The Netherlands |
|  B.V. Venlo TPN                                       |   | The Netherlands |
| ROW de Ruiter B.V.                                         |   | The Netherlands |
| Stationswijk B.V.                                          |   | The Netherlands |
| Heidemij Realisatie II B.V.                                |   | The Netherlands |
| Heidemij Realisatie I B.V.                                 |   | The Netherlands |
| Konijn Hoorn Machinebouw B.V.                              |   | The Netherlands |
| Copijn Utrecht B.V.                                        |   | The Netherlands |
| Copijn Utrecht International Tree Services B.V.            |   | The Netherlands |
| Copijn Utrecht Tuin en Landschapsarchitecten B.V.          |   | The Netherlands |
| Copijn Utrecht Eurobomen B.V.                              |   | The Netherlands |
| Copijn Utrecht Boomchirurgen B.V.BA                        |   | Belgium         |
| Copijn Luxemburg SA                                        |   | Luxembourg      |
| Atlantis GmbH                                              |   | Germany         |
| Grubbenvorst v.o.f.                                        |   | The Netherlands |
| KLM Aerocarto B.V.                                         |   | The Netherlands |
| Ilis B.V.                                                  |   | The Netherlands |
| KLM Aerocarto NV                                           |   | Suriname        |
| Transcad Ltd                                               |   | Egypt           |
| KLM Aerocarto Belgium B.V.BA                               |   | Belgium         |
| Assetrail B.V.                                             |   | The Netherlands |
| V.O.F. Modieslab                                           |   | The Netherlands |
| Autarcis B.V.                                              |   | The Netherlands |
| ARCADIS BMB Management Consultants B.V.                    |   | The Netherlands |
| Ilis/GMI B.V.                                              |   | The Netherlands |
| Ilis/Ilaco B.V.                                            |   | The Netherlands |
| Ingenieursbureau Grabowsky & Poort International  B.V. |   | The Netherlands |
| ARCADIS Caribbean N.V.                                     |   | Curacao         |
| ARCADIS St. Maarten N.V.                                   |   | St. Maarten     |
| ARCADIS Curaçao N.V.                                  |   | Curaçao    |
| ARCADIS Bonaire N.V.                                       |   | Bonaire         |
| Grabowsky&Poort Puerto Rico Inc.                       |   | Puerto Rico     |
| ARCADIS AQUMEN Facility Management B.V.                    |   | The Netherlands |
| ARCADIS Deutschland GmbH                                   |   | Germany         |
| ARCADIS Ekokonrem Sp.z.o.o.                                |   | Poland          |
| ARCADIS Belgium N.V.                                       |   | Belgium         |
| ARCADIS Holding France S.A.                                |   | France          |
| ARCADIS Geraghty & Miller International Limited        |   | United Kingdom  |
| Profil Sp. Z o.o.                                          |   | Poland          |
| ARCADIS Polska Sp. z o o.                                  |   | Poland          |
| ARCADIS Grabowski Grabowska                                |   | Poland          |
| ARCADIS UK Limited                                         |   | United Kingdom  |
| ARCADIS Consult GmbH                                       |   | Germany         |
| ARCADIS Bauconsult GmbH                                    |   | Germany         |
| ARCADIS Ingenieure Halle GmbH                              |   | Germany         |
| ARCADIS Liegenschaftsentwicklung GmbH                      |   | Germany         |
| ARCADIS HOMOLA AG                                          |   | Germany         |
| LGU Labor fur Geotechnik und Umwelt GmbH                   |   | Germany         |
| Dresdner Grundwasser Consulting GmbH                       |   | Germany         |
| ARCADIS Projektmanagement s.r.o.                           |   | Czech Republic  |

 

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| ECO2 Sp. z o o.                                     |   | Poland          |
|-----------------------------------------------------|--------|-----------------|
| Starke Diekstra N.V.                                |   | Belgium         |
| ARCADIS Gedas N.V.                                  |   | Belgium         |
| ARCADIS Lapere N.V.                                 |   | Belgium         |
| ARCADIS Fally N.V.                                  |   | Belgium         |
| ARCADIS Domus FM                                    |   | Belgium         |
| S.W.K. N.V.                                         |   | Belgium         |
| BCT scrl                                            |   | Belgium         |
| Ecolas N.V.                                         |   | Belgium         |
| Constructor N.V.                                    |   | Belgium         |
| CW N.V.                                             |   | Belgium         |
| Euras N.V.                                          |   | Belgium         |
| ARCADIS FCI S.A.S.                                  |   | France          |
| Europe Etudes Gecti (EEG)                           |   | France          |
| ARCADIS ESG                                         |   | France          |
| Sobesol                                             |   | France          |
| Geotechnika                                         |   | Czech Republic  |
| Mecasol                                             |   | France          |
| Eurometudes                                         |   | Rumania         |
| GOEFOS                                              |   | Slovakia        |
| Terence E Dudley & Associates                   |   | United Kingdom  |
| ARCADIS Chile S.A.                                  |   | Chile           |
| ARCADIS Brasil Ltda                                 |   | Brazil          |
| ARCADIS US Holding, Inc.                            |   | Delaware        |
| ARCADIS Geotecnica S.A.                             |   | Chile           |
| GC Consultores Geotecnicos                          |   | Peru            |
| Geotecnica Consultores Ltd                          |   | Argentina       |
| Arcadis Geotécnica Bouw Infra Ltda.            |   | Chile           |
| Consorcio Arcadis Geotecnica Mimetal Ltda.          |   | Chile           |
| Inversiones de Infraestructura Cabo de Hornos Ltda. |   | Chile           |
| ARCADIS Logos Ltda                                  |   | Brazil          |
| ARCADIS Logos Engenharia S.A.                       |   | Brazil          |
| ARCADIS Logos Energia S.A.                          |   | Brazil          |
| Enerconsult S.A.                                    |   | Brazil          |
| ARCADIS Hidro-Ambiente S.A.                         |   | Brazil          |
| ARCADIS Tetraplan S.A.                              |   | Brazil          |
| Biogás Energia Ambiental S.A.                  |   | Brazil          |
| PRC Training B.V.                                   |   | The Netherlands |
| ARCADIS Construction Consulting co, ltd             |   | Shanghai        |
| AYH ESOP Ltd                                        |   | United Kingdom  |
| AYH Sarl                                            |   | France          |
| AYH Homola Polska Sp zoo                            |   | Poland          |
| AYH Brown Ltd                                       |   | Scotland        |
| Summerfield Robb Clark Ltd                          |   | Scotland        |

** **

**NON-CONSOLIDATEDCOMPANIES**

 
| **Entity**                      | ** ** | **Jurisdiction** |
|---------------------------------|------------|------------------|
| Stichting Fagoed                |       | The Netherlands  |
| ARMADU Kromhout B.V.            |       | The Netherlands  |
| ARMADU Groningen B.V.           |       | The Netherlands  |
| EMDEME SA                       |       | Portugal         |
| Ecosystems B.V.                 |       | The Netherlands  |
| Combinatie Oost-Achterhoek B.V. |       | The Netherlands  |
| Urbanet B.V.                    |       | The Netherlands  |
| Combinatie ARCADIS NONAK V.O.F. |       | The Netherlands  |
| Combinatie De Ploen V.O.F.      |       | The Netherlands  |
| Stroomdal II                    |       | The Netherlands  |

 

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| Brainliner B.V.                                                            |   | The Netherlands |
|----------------------------------------------------------------------------|--------|-----------------|
| Vermeer-Heidemij v.o.f.                                                    |   | The Netherlands |
| Waterwolf Dienstverlening Buitenruimte B.V.                                |   | The Netherlands |
| Siberië CV                                                            |   | The Netherlands |
| Bio Science Park CV                                                        |   | The Netherlands |
| VOF Meinga                                                                 |   | The Netherlands |
| Eurotree GmbH                                                              |   | Germany         |
| Guard B.V. i.o.                                                            |   | The Netherlands |
| Adviseurs Bouwplan Ontwikkeling BGN Partners B.V.                          |   | The Netherlands |
| Aronsohn ARCADIS Oosterdokseiland VOF                                      |   | The Netherlands |
| Somerset                                                                   |   | Maryland        |
| Sahelconsult Sarl, Ouagadougou                                             |   | Burkina Faso    |
| Afid Consultants Sarl                                                      |   | Senegal         |
| Euroconsult para Latinoamerica y el Caribe SA.                             |   | El Salvador     |
| Brazilian Venture Consultants Ltda.                                        |   | Brazil          |
| Ilaco do Brazil Ltda.                                                      |   | Brazil          |
| Ilaco Suriname N.V.                                                        |   | Suriname        |
| Eurasia Consult Ltd                                                        |   | Kazakhstan      |
| Surgroma N.V.                                                              |   | Suriname        |
| CV Oude Grachtpad                                                          |   | The Netherlands |
| Umweltlabor Westpfalz GmbH                                                 |   | Germany         |
| Interplan Environmental Systems GmbH                                       |   | Germany         |
| Jaakko Poyry Geotecnica Ltd                                                |   | Chile           |
| Proyectos Aeroportuarios Ltd                                               |   | Chile           |
| ORSA                                                                       |   | Chile           |
| Consorcio Reg. GC JRI Ing. Ltda                                            |   | Chile           |
| Consorcio Scetaroute-Grimaux, Varde, Geotécnica  Ltda.                |   | Chile           |
| Consorcio Geotécnica JRI S.A.                                         |   | Chile           |
| PIE-RP Termelétrica S.A.                                              |   | Brazil          |
| Cocal Termelétrica S.A.                                               |   | Brazil          |
| Breitener Energética S.A.                                             |   | Brazil          |
| Hidropower Energia S.A.                                                    |   | Brazil          |
| Tupan Energia Eletrica S.A.                                                |   | Brazil          |
| Energética Ponte Alta S.A.                                            |   | Brazil          |
| V.O.F. Stationseiland                                                      |   | The Netherlands |
| V.O.F. De Ruijterkade                                                      |   | The Netherlands |
| V.O.F. X-Pact                                                              |   | The Netherlands |
| V.O.F. EMC STARC                                                           |   | The Netherlands |
| Geodynamique et Structure                                                  |   | France          |
| Getu                                                                       |   | Tunisia         |
| SEM Savoie Labo                                                            |   | France          |
| Geomechanika, s.r.o.                                                       |   | Czech Republic  |
| Solidex, a.s.                                                              |   | Czech Republic  |
| Kamex, s.r.o.                                                              |   | Czech Republic  |
| Geoprojekt, s.r.o.                                                         |   | Czech Republic  |
| Terratech, spol. S.r.o.                                                    |   | Czech Republic  |
| Terratec, spol. S.r.o.                                                     |   | Czech Republic  |
| Geoinzenyring, s.r.o.                                                      |   | Czech Republic  |
| ZPD d.d.                                                                   |   | Croatia         |
| The GIS Foundation Partnership (Joint Venture)                             |   | North Carolina  |
| ARCADIS/BPA- Joint Venture                                                 |   | Georgia         |
| Global Rail Consortium LLC                                                 |   | Florida         |
| Encore Environmental Consortium, LLC                                       |   | Michigan        |
| Environmental Engineering Associates, LLP                                  |   | New York        |
| Blasland, Bouck & Lee/TAMS Consultants, Inc.  (New York Joint Venture) |   | New York        |
| CTI/AGM (Joint Venture)                                                    |   | Tennessee       |
| Arcadis/Geotechnical Consultants, Inc.                                     |   | California      |
| Bioengineering ARCADIS LLC                                                 |   | Louisiana       |
| LSR Joint Venture                                                          |   | Maryland        |

 

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| PinnacleOne/Barnhart, Inc.                                          |   | Arizona        |
|---------------------------------------------------------------------|--------|----------------|
| ARCADIS G&M of North Carolina, Inc.                             |   | North Carolina |
| ARCADIS G&M of New York Architectural and  Engineering Services |   | New York       |
| GMCE, Inc.                                                          |   | Florida        |
| Construction Dynamics Group P.C.                                    |   | Maryland       |
| Robert Shanks Projects Ltd                                          |   | United Kingdom |
| Noble Projects Management Ltd                                       |   | United Kingdom |
| Berkeley Consulting Ltd                                             |   | United Kingdom |
| Homola AYH Ltd                                                      |   | United Kingdom |
| SMP / AYH Ltd                                                       |   | Ireland        |
| AYH Mace Ltd                                                        |   | United Kingdom |

 

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