What Sieker does

Sieker (legally Ingenieurgesellschaft Prof. Dr. Sieker mbH) is a German engineering bureau headquartered in Hoppegarten near Berlin, founded around 1999. The firm specializes in stormwater management, wastewater treatment, river rehabilitation, and flood protection, serving primarily municipal governments and public-sector clients across Germany and selected international markets (Norway, Saudi Arabia, Nicaragua). It is led by founder Prof. Dr.-Ing. Heiko Sieker with a small team of doctoral-credentialed engineers and operates with 1-10 employees as an independent, privately held GmbH with no external investors or parent company.

The company's technical offering spans four interlocking layers. The software layer centers on the proprietary STORM hydrological runoff model, originally developed for Sustainable Urban Drainage Systems (SUDS) design, and FLEXT, a Flexible Expert Tool for stormwater modeling and design. The planning layer covers river basin management, master planning, drainage concepts, and hydraulic computation. The technical-products layer includes the Innodrain retention/infiltration/evaporation/treatment system, the Innolet filter gully, and storm tree pit systems. The information layer consists of an unusually comprehensive public technical library covering runoff control, infiltration, rainwater harvesting, treatment, and flood protection. Sieker has also participated in multiple EU Framework Programme research collaborations (SWITCH, TRUST, KURAS) funded by the European Commission and BMBF.

Sieker's business model combines professional services revenue (consultancy, planning, research, training) with hardware sales (Innodrain line) and software licensing (STORM, FLEXT). Distribution is direct, sales-led, and project-driven, with the website (sieker.de) — published in ten languages — serving as the primary marketing channel supplemented by conference presence at ICUD and IFAT. Quantitative project outcomes cited include a 37% reduction in combined sewer overflow (CSO) frequency through SUDS implementation. Customers are almost exclusively public-sector entities — Hamburg Department of Environment and Energy, Stadt Baden-Baden, BMBF, Land Brandenburg, Stadt Teltow, Bezirksamt Hamburg-Harburg, Stadt Kempten, Flussbad Berlin, and TU Delft — giving the firm a concentrated but stable revenue profile anchored in long-cycle municipal infrastructure work.

Name

Sieker

Legal name

Ingenieurgesellschaft Prof. Dr. Sieker mbH

Website

https://sieker.de

Company type

Private

Founded year

1999

Operating status

Operating

Headcount range

1–10 employees

Short description

Sieker is a German engineering bureau (Ingenieurgesellschaft Prof. Dr. Sieker mbH) founded in 1999 and headquartered near Berlin, offering consultancy, planning, proprietary hydrological software, and technical drainage products for stormwater management, flood protection, and wastewater treatment to municipal governments and public-sector clients in Germany and selected international markets.

Ownership category

akta.pro rank

Product category

Environmental and Water Engineering Services

NAICS

Engineering Services (541330)

SIC

Services-Engineering, Accounting, Research, Management (8700)

akta.pro primary industry

Real-Time Monitoring & Smart Stormwater (Sensors, SCADA/IoT, RTC) (EUANAEAK)

akta.pro secondary industries

Water & Wastewater Compliance (NPDES/Stormwater, Pretreatment, Drinking Water/SDWA) (EUAHABAB), Water, Wastewater & Stormwater Compliance (BPAHAJAJ), Stormwater & Drainage Infrastructure Construction (Sewer, Detention, Outfalls) (IMAFAGAF)

Keywords

• Stormwater management
• Flood protection engineering
• Hydrological modeling software
• Urban drainage systems
• Water engineering consulting

Headquarters

HQ city

Hoppegarten

HQ country

Germany

HQ region

Europe

Offices1 record

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Technology or R&D, Operations, Marketing or Sales

Revenue model

1. Consultancy Services: Professional engineering consultancy services in stormwater management, wastewater treatment, flood protection, and river rehabilitation.
2. Planning Services: Engineering planning services including river basin management, stormwater management planning, flood protection planning, and drainage concepts.
3. Technical Products: Sale of technical products including Innodrain, Innolet, and Storm tree pit systems for stormwater treatment and management.
4. Software Licenses: Software products including STORM model and FLEXT for hydrological modeling, design and GIS applications.
5. Research Services: Research and development services, often funded through EU research programs (EU Framework Programmes, BMBF).
6. Training: Training services on stormwater management topics.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels3 records

Core offering

Sieker (Ingenieurgesellschaft Prof. Dr. Sieker mbH) is a German engineering bureau offering consultancy, planning, and technical services in stormwater management, wastewater treatment, river rehabilitation, and flood protection. The firm sells proprietary technical products (Innodrain, Innolet, storm tree pit systems) for decentralized rainwater management and licenses its own hydrological modeling software (STORM and FLEXT). It combines engineering project expertise with research-driven know-how for municipalities, government agencies, and urban development projects.

Product overview

Sieker is an engineering bureau (Ingenieurgesellschaft Prof. Dr. Sieker mbH) offering consultancy services and products in stormwater management. The company operates a platform-plus-services model with core offerings including Planning Services (river basin management, stormwater infrastructure planning), Technical Products (Innodrain, Innolet, storm tree pit systems for retention/infiltration/treatment), Software Products (STORM hydrological modeling software, FLEXT expert tool), Consultancy Services, Research & Development, and Training. They combine engineering project expertise with theoretical research know-how, providing comprehensive solutions from planning through technical implementation.

Differentiator

Problem solved

Functional benefit

Products and services

• Planning Services Engineering planning services for storm water management and flood protection based on latest state-of-art technologies, including river basin management and master planning. Sold to municipalities, government agencies, and urban development clients.
• Consultancy Services Expert consultancy in stormwater management, wastewater treatment, river rehabilitation, and flood protection. Provided to municipalities, government agencies, and urban development projects.
• Technical Products (Innodrain, Innolet, Storm Tree Pit) Hardware product line for decentralized stormwater management including Innodrain (trench/swale retention-infiltration system), Innolet filter gullies, and storm tree pit systems for retention, infiltration, evaporation, and treatment of rainwater. Sold to municipalities, developers, and engineering contractors.
• Software Products (STORM, FLEXT) Licensed hydrological modeling and GIS software including STORM (a hydrological runoff model covering the full hydrological cycle for catchments and SUDS design) and FLEXT (Flexible Expert Tool) for design and analysis of water-related systems. Licensed to engineers, municipalities, and researchers.
• Research Services R&D services combining research skills with engineering project expertise to provide theoretical know-how for stormwater management solutions. Often funded through EU Framework Programmes (e.g., SWITCH, TRUST) and BMBF (e.g., KURAS). Delivered to research consortia, public agencies, and academic partners.
• Training Services Professional training and educational services on stormwater management and water engineering topics. Delivered to municipalities, engineers, and other professionals seeking continuing education in decentralized stormwater management.

Quantifiable outcome

• Combined sewer overflow (CSO) frequency reduction by 37% through SUDS implementation
• +1 more outcomes

Named customers9 records

Segments2 records

Ideal customer profiles2 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Scale indicators2 records

Recent moves6 records

Expansion highlights5 records

Broad incumbents

• Ramboll: Global engineering consultancy with a large water and environment practice covering stormwater, flood, and climate adaptation. Competes for the same German and Nordic municipal tenders as Sieker but at much larger scale and scope.
• Sweco: European engineering and architecture consultancy with strong water, environment, and climate adaptation offerings across Germany and the Nordics. Directly competes for municipal master-planning work.
• Arcadis: Global design and consultancy firm with a substantial water management and climate resilience practice. Often wins large integrated water/urban planning contracts that Sieker would otherwise chase as a specialist sub-consultant.

Direct peers

• HR Wallingford: UK research-led hydraulics and water engineering organization offering consultancy, software, and physical modeling for stormwater, flood, and coastal projects. Mirrors Sieker's research-plus-engineering bureau model.
• Hydro International: Provider of stormwater treatment and management products (downstream defenders, vortex separators). Comparable to Sieker's Innodrain/Innolet/Storm tree pit hardware line serving similar municipal customers.
• DHI A/S: Denmark-based water modeling and engineering firm behind the MIKE suite of hydrological and hydraulic software. Closest peer in combining proprietary modeling software (STORM-equivalent) with stormwater and flood consulting services.
• Hydrotec Ingenieurgesellschaft: German engineering consultancy focused on hydrology, flood protection, and urban water management with proprietary modeling tools. Directly comparable to Sieker in services, geography, and customer base (German municipalities).

Others

• ACO Ahlmann: Major German manufacturer of drainage, stormwater management, and surface water treatment systems. Complementary rather than competitive — ACO is a potential channel partner or competitor to Sieker's Innodrain hardware line.
• Rehau: Manufacturer of stormwater management and building infrastructure products including infiltration and retention systems. Overlaps with Sieker's technical product portfolio and serves the same municipal customers.
• Wavin: Global provider of plastic pipe and stormwater management solutions including infiltration and attenuation crates. Adjacent ecosystem player whose products can be specified within Sieker's drainage concepts.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat3 records

Key risks7 records

Key highlights7 records

Customer concentration

• Xx.com/ing_sieker
• LinkedInlinkedin.com/company/ingenieurgesellschaft-prof.dr.-sieker-mbh

Revenue estimate

Valuation estimate

Number of profiles

Profiles6 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Sieker