Hydraulic sizing, automatic IOTA classification and generation of Water Law filings (DLE) and hazard studies (GEP). Compatible with field measurements imported from Porchet Test Modeling. PDF deliverables ready to submit to the reviewing authority.
International availability — the automatic retrieval of geological and piezometric data (BRGM, Hub'Eau) covers France. For a project located in another country, these parameters must be entered manually by the user; the automation of this retrieval by country is under development.
Retention / infiltration basins, controlled discharge. Calculation of the useful volume (V_useful) and critical volume (V_critical), leak flow rate, allowable flow rate, Montana coefficient by climate zone.
Article R.214-1 of the Environmental Code. Automatic determination of the regime (declaration / authorization) with respect to headings 2.1.5.0, 3.3.1.0, 3.2.2.0 and 1.1.1.0.
Water Law filing (Articles L.214-1 to L.214-6 of the Environmental Code), structured for submission to the DDT(M). Dynamic title block: reference, revision, prepared by / reviewed by, city, date.
Hazard study for infiltration: reasoned technical note (permeability, hydrogeological impact, environmental legacy), WFD water body, geological formation.
Diagram of the water flow path and retention basin. Location maps (IGN Géoplateforme, BRGM, WFD water bodies, ZNIEFF, Natura 2000).
Direct import of field measurements entered in Porchet Test Modeling to compare the measured K with the theoretical K used in the GEP sizing.
A site's suitability for stormwater infiltration depends on its environmental history. The software incorporates this legacy as an alert criterion and a decision aid between infiltration, retention, treatment, controlled discharge or further investigations.
On an SIS site or former industrial brownfield, stormwater infiltration can mobilize surface pollution towards groundwater. The software flags this risk and directs the modeling towards a suitable strategy: priority retention, sealing, treatment, controlled discharge or further investigations.
Automatic cross-referencing of SIS / BASOL / BASIAS / ICPE with geological data (BRGM) and hydrogeological data (WFD water body) to decide between infiltration, retention and controlled discharge based on site sensitivity.
The GEP module natively integrates the results of Porchet Test Modeling (dedicated tool, available separately) to qualify infiltration suitability based on field measurements rather than on the BRGM bibliographic estimate alone. It cross-references the available geological, hydrogeological, historical, bibliographic and environmental data to strengthen the reliability of the permeability value used for sizing.
When a field Porchet test is available, the measured K prevails over the BRGM bibliographic estimate for sizing the infiltration structure, provided the two values are consistent (log10 deviation ≤ 0.5). In the absence of a field test, the software uses the BRGM bibliographic value for the relevant geological formation. Whether to carry out an in-situ test remains a matter of judgment based on the level of uncertainty, site sensitivity, environmental legacy, local requirements and the expectations of the reviewing authority.
The software does not replace the engineer's expertise, nor any requests from the DDT(M), the DREAL, the project owner or the inspection body.
Water Law regime applicable to Installations, Structures, Works and Activities (IOTA) — Articles L.214-1 to L.214-6 of the Environmental Code. The authorization / declaration regime is defined by Article R.214-1 of the Environmental Code and its nomenclature.
| IOTA heading | Subject | Thresholds (declaration / authorization) |
|---|---|---|
| 2.1.5.0 | Discharge of stormwater into surface freshwater, onto the ground or into the subsurface | Criterion: total project area plus intercepted natural catchment — Declaration > 1 ha and < 20 ha; Authorization ≥ 20 ha |
| 3.3.1.0 | Draining, flooding, sealing or filling of wetlands or marshes | Declaration > 0.1 ha and < 1 ha; Authorization ≥ 1 ha |
| 3.2.2.0 | Installations, structures or fill in the floodplain of a watercourse (area removed from flood expansion) | Declaration ≥ 400 m² and < 10,000 m²; Authorization ≥ 10,000 m² |
| 1.1.1.0 | Drilling, boring, creation of wells or non-domestic underground structures (groundwater investigation / monitoring / abstraction) | Generally declaration — to be reviewed if boreholes, piezometers, pumping tests or associated structures are planned |
Thresholds and regimes (declaration / authorization) must be verified case by case on Légifrance and with the reviewing authority. The classification proposed by the software is a decision aid and does not prejudge the administrative review.
Water Law filing (L.214-1 to L.214-6 of the Environmental Code), structured for submission to the DDT(M). Dynamic and editable title block data.
Hazard study for infiltration, reasoned note: permeability, hydrogeological impact, environmental legacy.
Diagram of the water flow path / retention basin. Reports generated in PDF format, ready to transmit.
| Scope | Indicative timeline |
|---|---|
| Pre-analysis and IOTA classification | 24 to 48 h |
| Standard DLE / GEP report (low-sensitivity site) | 3 to 5 business days |
| Complex file (sensitive site, wetland, industrial legacy, exchange with the reviewing authority) | 7 to 15 business days |
Indicative GMEP production timelines, after receipt of complete project data. They do not prejudge the administrative review timelines set by the DDT(M) or the DREAL.
Annual subscription — 1 seat
French VAT at the standard rate of 20% (Art. 278 of the CGI).
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Training, custom configuration or personalized regulatory support: on request — contact GMEP.