Engineering office for water & environment · Heinsberg, NRW

Use water, soak it away, treat it naturally.Planned, calculated and ready to submit.

Whether it's a cistern for the garden, a natural pool or a constructed wetland: you describe your project in your own words — we take care of the engineering, the calculations and all the proofs and verifications it needs, signed off by a registered engineer under professional responsibility. Price and turnaround are fixed in writing before you commission us.

Free initial consultationWhat we deliver
Orientation

What brings you to us?

Six typical starting points — you don't have to translate any of them into standards; that's our job:

Converted stone farmhouse with a natural pond and reed zone — water as part of the property

“My building application is missing the rainwater infiltration proof.”

Routine for us: we produce it ready to submit and sign off on it — you just attach it.

Infiltration verification (Versickerungsnachweis)

“Why am I paying for drinking water to water the garden?”

A cistern for garden, WC and washing machine — with an honest calculation of whether it pays off.

Rainwater harvesting

“I would love a natural pool or swimming pond.”

Clear water without chlorine — properly designed; we check whether a permit is needed at all.

Natural pools & ponds

“My property has no sewer connection — the old septic tank has to go.”

A constructed wetland: a planted bed instead of machinery, barely any electricity — planned ready to submit.

Constructed wetlands

“My documents came back with queries.”

Common and fixable: we review the verification and tell you in writing what is missing.

Plausibility review

“After a downpour, the water comes right up to the house.”

Swales, trenches and retention to recognised codes of practice — the water stays where it does no harm.

Heavy-rain protection

“I want to make my property greener and climate-proof.”

Green roof, de-sealing, rain retention — cools in summer, buffers downpours, often subsidised.

Sponge city & green roofs

“I'm an architect or landscaper — my project is stuck on the water planning.”

White-label or visible specialist planner: you keep the client — the planning is ours to sign.

For architects & landscapers

Your situation isn't listed? That's exactly what the free initial consultation is for: you tell us about your project — we tell you what it needs, and what it doesn't. 30 minutes, no obligation.

Free initial consultation
I am...

Your DWA compliance backbone.

You design buildings. We deliver the water hydraulics — review-ready and ready to submit, as a silent partner or under your name. You keep the client relationship.

For architects
  • Infiltration verifications to DWA-A 138-1 — submitted by you; the proof always carries the responsible engineer's signature
  • Water balance to DWA-M 102-4
  • Retainer from €600/month
Services

Three problems. Three clean solutions.

Every engagement ends with a concrete, permit-ready document — signed, stamped, with a statement of conformity with the applied standard. Fixed-price offer within 24 hours.

Urban bioswale running alongside a residential street — infiltration-active planting channel per DWA-A 138-1

“Your building application is waiting on the infiltration proof.”

Infiltration & Heavy-Rainfall Protection

Proof of infiltration per DWA-A 138-1, water balance per DWA-M 102-4, heavy-rainfall provision and swale-trench (soakaway) systems. Infiltration is in many cases a permit-required use of a body of water — whether your project falls under this is one of the first things we clarify. The authority expects a verifiable design for which an engineer takes responsibility. In the case of discharge into a body of water, we supplement the assessment with proof for fine suspended solids (AFS63) per DWA-A 102-2 and the treatment sizing per DWA-M 179-1.

What you get
  • Signed and stamped calculation dossier (PDF, 4–8 pages)
  • DWA-A 138-1 statement of conformity with the applied standard
  • KOSTRA-DWD data extract for your location
  • Dimensioned swale-trench site plan (DWG + PDF)
  • Authority submission checklist
  • AFS63 emission assessment per DWA-A 102-2 (where relevant)
Delivery time
Standard cases often within a week — deadline binding in the quote
Fixed price
from €700 net (from €833 incl. VAT)
Standards
DWA-A 138-1 · DWA-M 102-4 · DWA-A 102-2 · DWA-M 179-1 · KOSTRA-DWD
View details
Green courtyard of a residential block with rainwater management

“Water costs are the underestimated overhead trap.”

Rainwater Harvesting & Greywater

Full-scope planning for rainwater harvesting (cistern, toilet flushing, garden) and greywater recycling. Compliant design per DIN 1989 and DIN EN 16941-2 — with a project-specific cost-effectiveness analysis as part of the planning.

What you get
  • Hydraulic calculation with demand assessment
  • Cistern sizing and component list
  • Connection and distribution plan (DWG + PDF)
  • Filter and treatment specification
  • Maintenance and operating instructions
Delivery time
often 1–2 weeks — deadline binding in the quote
Fixed price
from €700 net (from €833 incl. VAT)
Standards
DIN 1989 · DIN EN 16941-2 · DWA-M 277
View details
Natural swimming pond with a clear shallow-water zone and planted regeneration area — chemical-free water treatment

“A treatment plant that looks like a garden.”

Constructed Wetlands & Natural Pools

Our core competency. Biological treatment plants for properties without a sewer connection, natural swimming ponds, biological filter systems. Proven methods per DWA-A 262 and FLL — designed by an engineer who understands the biology behind them (M.Sc. Bionics). And it creates habitat along the way: your treatment system becomes the greenest part of the garden.

What you get
  • Complete planning dossier (30–60 pages)
  • Substrate sizing and layer structure
  • Planting plan with species list and planting densities
  • Hydraulic load calculation
  • Monitoring and maintenance concept
  • Construction specifications
  • FLL-compliant waterproofing (for natural pools)
Delivery time
often 2–4 weeks — deadline binding in the quote
Fixed price
from €1,200 net (from €1,428 incl. VAT)
Standards
DWA-A 262 · DWA-A 178 · FLL 2017 · DWA-A 222
View details

Net prices plus 19% VAT; bracketed figures are gross prices incl. VAT for private clients. Processing begins once documentation is complete. The fixed price applies to the scope defined in the quote. If investigations reveal new requirements or your concept changes, you receive an updated fixed-price quote before we continue — we never proceed without your approval.

  • Chamber of Engineers NRW
    Registered engineer · No. 754661
  • Professional liability insurance
    Insured design services — details in the legal notice
  • Qualification
    B.Sc. Industrial Engineering · M.Sc. Bionics
  • Recognised codes of practice
    Design per the applicable standards (DWA · FLL · FBR · VDI · DIN)
Why EKOWAI Engineering

Precision meets biological thinking.

Large offices master DWA hydraulics but don't know the biology. Specialists know the biology but don't deliver permit-grade calculations. We combine both in one office.

Timber boardwalk over a densely planted constructed wetland — nature-based water treatment
Biology and engineering design in one system.
01

Proven technology, biologically informed.

Constructed wetlands and nature-based water systems are proven methods under recognised codes of practice (DWA, FLL) — not experiments. We design them with an understanding of the biology behind them (M.Sc. Bionics). This blend of biology and engineering design is the core of our firm.

02

Approvable through standards compliance

More than 14 DWA standards on file. Every calculation follows the Generally Accepted Rules of Technology, every design parameter with a source reference — the authority can verify every value. And a registered engineer signs off with full responsibility.

03

Direct. Reliable. Personal.

A quote within 24 hours, a fixed price with no hourly risk, and you always speak with the responsible engineer — not with a clerk who has to check back. The planning sector is at its capacity limit (IW survey 2025); we keep the lines of communication short.

Why not a large office? Compare.

Processing time

Large offices
typically 4–8 weeks
DIY
–
EKOWAI Engineering
Binding in the quote — standard cases often within a week*

Direct contact with the engineer

Large offices
Rarely
DIY
–
EKOWAI Engineering
Always

Responsibility & liability for the design

Large offices
With the firm
DIY
With you
EKOWAI Engineering
With us — signed off under our responsibility

Fixed price

Large offices
Rarely
DIY
–
EKOWAI Engineering
Standard

Nature-based systems (constructed wetlands, natural pools)

Large offices
Generalist
DIY
None
EKOWAI Engineering
Core competency

Statement of conformity with the applied standard to the applicable code

Large offices
Yes
DIY
–
EKOWAI Engineering
Yes — with a source reference for every design parameter

*Standard cases, once documentation is complete.

For Architects

Architect? We are your DWA back-office.

Architects love designing, but no one enjoys hour-long DWA hydraulic calculations. We take over the water-specific compliance — as your silent background partner or as a visible co-engineer. You keep the client relationship.

  • Infiltration proofs and water balances — submitted by you; the proof always carries the responsible engineer's signature
  • Sizing checks and code compliance reviews by email or phone
  • Water authority communication on request — optional, commissioned separately
  • Monthly retainer or per-project engagement — you choose
For landscaping firms & landscape architects

Your client wants the pond from you. The authority wants an engineer. We're yours.

You keep the client relationship and the construction contract — we deliver the sizing, the FLL-compliant sealing concept and the approval documents, signed off under professional responsibility. Reachable during construction, so nothing gets lost between plan and execution.

The maths is simple: the planning costs a few percent of the project budget — and makes sure permit and execution fit together.

Discuss a partnership

Three steps to submission.

  1. Free of charge

    Initial consultation

    30 minutes by video call, free of charge. We clarify your project, the applicable standards, the responsible water authority — and which documents you are still missing.

  2. Within 24 h

    Fixed-price quote

    In writing within 24 hours: scope of services, deliverables, turnaround time from complete documentation, one figure. No hidden costs.

  3. Binding

    Planning & handover

    Review-ready documents with a statement of conformity with the applied standard, signed under professional responsibility — ready to submit directly to the authority. On request, we continue to support the procedure: follow-up questions, supplementary submissions, and coordination of any required investigations.

Urban district with Sponge City elements: unsealed surfaces, swales and planting
Sponge City in the neighbourhood — unsealed surfaces, swales and planting keep rainwater on site.
Why now

EU law is ticking. Funding windows open.

Demand for water-sector engineering services is not cyclical — it is legally forced. In NRW alone, over 10,000 individual measures are planned in the 2022–2027 management plan, with a volume of around €3.7 billion (MUNV NRW). Under the adopted amendment to the Climate Adaptation Act (transposition planned for 2027), all 396 NRW municipalities are to submit climate adaptation concepts by the end of 2029 — only around 100 have one today (MUNV NRW). Only 9.4% of NRW flowing waters currently reach the required good ecological status (NRW/LANUV environmental indicators, 2018–2021 survey).

While around 300 NRW municipalities still lack a climate adaptation concept, demographic change is tightening the bottleneck further: the 2025 German water sector industry picture describes a worsening shortage of skilled workers as a central challenge for the sector. The regulatory direction is set. Firms and municipalities that plan now won't later be competing for residual capacity — the planning sector is already at its limit (IW survey 2025, n > 2,500 firms).

Sources
  • Management plan 2022–2027 — MUNV NRW
  • Climate report 2024 — LANUK NRW
  • Water bodies report 2024 — LANUV
  • German water sector industry picture 2025 — BDEW/DVGW
Sustainability & circular economy

Your bank is asking for ESG data? We turn that into a report — and a plan.

VSME sustainability report for small and medium-sized companies, a CO₂ balance with a source reference for every figure — and circular-economy measures an engineering office plans rather than just recommends: use rainwater, recycle greywater, unseal surfaces.

More on sustainability & VSME
Knowledge

Practical guides on water planning.

Written by the engineer who runs the calculations — no PR copy, no sales talk. Knowledge that helps you directly with your project.

Article 1

Infiltration proof NRW: what the water authority checks in 2026

What must a DWA-A 138-1 infiltration proof contain? Which mistakes lead to rejection? A step-by-step guide from the engineer who writes them daily.

Read

We only publish articles when they are truly finished. More guides follow after release.

How we work.

Who is responsible for the planning?
Alvaro Burgos Cifuentes, M.Sc., a registered member of the Ingenieurkammer-Bau NRW (Nr. 754661), with professional indemnity insurance covering the planning services. Insurance details: see the About page and the legal notice. All calculations and plans are personally reviewed, signed and stamped.
How long does an infiltration verification actually take?
We often deliver standard cases within a few working days — counted from the day on which the site plan and soil survey are fully available. More complex cases (hybrid systems where infiltration conditions are poor) take correspondingly longer. Your processing time is stated bindingly in the quote — before you commission.
What does infiltration planning typically cost?
Infiltration verifications from €700 net (€833 incl. VAT) for the concept and from €1,500 net (€1,785 incl. VAT) for the full design, the plausibility review of an existing verification €600 net (€714 incl. VAT) — each as a fixed price. Complex constructed wetlands and integrated water concepts fall within the mid to high four-figure range. You will receive the binding fixed price for your property within 24 hours of the initial consultation.
What happens if my project changes along the way?
The fixed price always refers to the scope described in the quote. If soil investigations show different conditions than assumed, or you decide on a different concept (say, a constructed wetland instead of a natural pool — a different code then applies), we pause and you receive an updated fixed-price quote within 24 hours. Work already delivered is billed as quoted. You never pay anything that wasn't fixed in writing beforehand. And if the concept turns out not to be feasible: finding that out is exactly what the concept stage is for — you get a reliable, signed answer before you invest in the full design.
Do you also work outside NRW?
Our focus is the Niederrhein corridor and NRW as a whole — from our office in the Heinsberg district, the Dutch border region is close by. We also take on projects in the Rhine corridor (Cologne, Düsseldorf, Bonn). Nationwide projects are generally possible, though with a travel-cost share.
Can you also handle the water authority procedure?
Yes, optionally. The standard service includes authority-ready documents — submission is handled by the client or architect. On request, we take over direct communication with the responsible water authority, follow-up submissions and queries. This service is billed separately according to effort.
What performance do your systems actually deliver?
All of our designs meet the performance requirements of the respective DWA standard — the specific efficiencies (e.g. COD reduction under DWA-A 262, suspended-solids separation under DWA-A 178) are defined in the standards and precisely documented in every planning document. We provide project-specific performance forecasts with source references as part of the planning.
Do you offer further specialised services?
Yes — field measurements, funding-application support, cost-effectiveness analyses and project-specific special services are provided by arrangement. We're also happy to discuss process- and wastewater questions for commercial operations — such as food processing, breweries or aquaculture — in the initial call; here we plan according to the relevant DWA guidelines. Simply get in touch if your project has particular requirements.
Alvaro Burgos Cifuentes, M.Sc. — responsible engineer at EKOWAI Engineering, HeinsbergFree · No obligation · 30 minutes

Talk to the engineer.

No call center, no sales team. You reach Alvaro Burgos Cifuentes, M.Sc. directly — responsible for every project from inquiry to handover.

Book a call directlyor send an email
  • Fixed price — one number, no hidden costs
  • Signed off under professional responsibility, insured planning services
  • Directly with the engineer