the empuriabrava wastewater treatment plant and constructed

THE EMPURIABRAVA WASTEWATER
TREATMENT PLANT AND CONSTRUCTED
WETLAND SYSTEM
Enric Pallarès
Consorci de la Costa Brava
3rd Wetland Pollutant Dynamics and Control Symposium
WETPOL 2009
El Cortalet, Aiguamolls de l’Empordà, 23 September 2009
Environmental reuse project
• Mid 90’s - Need of a new source of
water for the Aiguamolls de l’Empordà
Nature Reserve
• New WWTP in Empuriabrava (1995),
– In the south side of Mega River
– Where Nature Reserve is located
• Secondary effluent is proposed as
alternative source
• Nutrient –specially nitrogen- removal is
needed
– Reclamation through a constructed wetland
system
• Constructed wetland system:
– to provide the treatment
– potential interesting habitat by itself
WWTP and
Wetland
System
Visitor
Center
(Cortalet)
Goals of the project
• Supply water in the 18-ha manmade
Cortalet lagoon
–
to avoid its summer desiccation
– and/or to restore wet meadows in the
surrounding area
– to avoid the eutrophication
• removal of nutrients needed!
• Reduce discharges in the nearby
Muga river
• Preservation of the local habitats and
their specific flora and fauna
Application of polished effluent
Wet
Meadows
Visitor
Center
Cortalet
Lagoon
Empuriabrava WWTP
• In operation since 1995, it services the
touristic community of Empuriabrava municipality of Castelló d’Empúries
• Range of treated flows (m3/day):
– winter, low season: 1,500
– summer, peak season: 6,500
• Extended aeration (N/DN) + settling tanks
+ Sludge sedimentation ponds + Polishing
ponds
• Originally, two independent treatment
lines; a third one added in 2007
• Chemical phosphorus removal added
recently
The Empuriabrava constructed
wetland system
• In operation since 1998
• Project funded by EU Cohesion
Funds (80%) and CCB (20%):
– Constructed wetland:
• 3 treatment cells of 0,8 ha each
• shallow lagoon of 4,5 ha
• (total, approx. 7 ha).
– Pumping station
– 2 km pipeline to deliver reclaimed
water to the Parc Natural dels
Aiguamolls de l’Empordà (PNAE).
– Pedestrian bridge on the Muga
river to connect urban area of
Empuriabrava with PNAE.
The constructed wetland system
• Set in operation since 1998
• 3 vegetated cells
–
–
–
–
160 m x 50 m: 8,000 m2
average depth of 0.5 m
cattail -Typha latifoliareed -Phragmites australis-)
• Shallow pond: Estany Europa
–
–
–
–
average depth 0.2 m
Surface of 45.000 m2
additional treatment
ecosystem diversity for flora and fauna
Diagram of the facilities
Operation of the system
• 2000-2008:
- Average of 78 % of the treated
wastewater treated through the
wetland system and recycled for
environmental purposes
- 737.000 m3/year out of 940.000
m3/year ⇒ not discharged to the
Muga river
- Since 2007, almost all the flow is
reused thanks to the new third
biological reactor
Performance of the System
some of the results
– Evaluated according to the removal of
total inorganic nitrogen (TIN)
– Nutrient loads (concentration x flow)
calculated for both system inlet and
outlet
– Removal of 85% of the TIN in 2008
(approx. 6,300 kg N)
– Estimations of P removal show greater
annual variability; in 2008, 47% of total
phosphorus
(approx. 2,700 kg P)
Other results:
Visitors are welcome