The client challenge
La Ciotat Shipyards (formerly SEMIDEP) operates a port platform of more than 4 hectares dedicated to the maintenance and careening of mega-yachts of more than 4,000 tonnes, lifted from the water by one of Europe's most powerful boat lifts. The site accommodates 8 simultaneous work stations for careening, hull maintenance and surface treatment operations.
These activities generate runoff and careening water particularly loaded with pollutants specific to the port environment:
- Hydrocarbons: oils, fuels and lubricants from engine maintenance operations
- Antifouling paints: hull stripping residues containing biocides (copper, zinc, tributyltin in older coatings) and heavy metals
- Suspended solids (TSS): blasting fines, paint residues, various particles from hull cleaning
- Stormwater runoff: rainwater collected across the entire impervious platform
Subject to the Vague Bleu Carénage reference framework — the reference environmental standard for careening zones in France — La Ciotat Shipyards needed to implement a treatment system capable of meeting the demanding performance requirements of this specification, particularly for metals, hydrocarbons and TSS.
Nomado designed, built and operated two compact treatment units to cover all flows on the site.
The Nomado solution
Nomado designed and deployed two compact, complementary treatment units, incorporating an advanced 6-stage physico-chemical process, adapted to the specific characteristics of mega-yacht careening water.
Our approach combined Vague Bleu Carénage-compliant treatment performance, compactness on a constrained site, and integrated operation over 3 years.
Advanced physico-chemical treatment process
The complete system treats a flow rate of 7 to 21 m³/h depending on weather conditions and the intensity of careening operations.
Collection and pre-separation
- Pumping equipment for water collection: intake of runoff and careening water collected across the platform
- Grit trap: separation of coarse sludge and floating waste (paints, free hydrocarbons) at the process inlet
Physico-chemical treatment
- Coagulation-flocculation: destabilisation and agglomeration of fine particles, dissolved metals (copper, zinc) and antifouling paint residues into separable flocs
- Lamellar settling: accelerated separation of flocs by gravity, with continuous sludge extraction
Multi-barrier filtration
- Sand and activated carbon filtration: removal of residual suspended solids and adsorption of dissolved hydrocarbons, organic residues and traces of biocides
- Microfiltration: final barrier guaranteeing compliance with Vague Bleu Carénage limit values for TSS and metallic parameters
Integrated operation over 3 years
- Full design study: sizing adapted to the variable flow rates of the site (7 to 21 m³/h)
- On-site commissioning by Nomado teams
- Operation, maintenance and analytical monitoring carried out by Nomado for 3 years to ensure continuous compliance with the Vague Bleu Carénage standard
Results achieved
- Compliance with the Vague Bleu Carénage standard achieved and maintained throughout the operational period
- Treatment of 7 to 21 m³/h of careening and runoff water, covering all flows from the 4-hectare platform
- Two compact containerised units integrated on a space-constrained port site
- Complete 6-stage process guaranteeing performance across all careening-specific pollutants: TSS, metals (Cu, Zn), hydrocarbons, biocides
- La Ciotat Shipyards strengthens its positioning as an environmentally responsible shipyard — an essential condition for attracting owners of high-end mega-yachts
