Dam dewatering

Challenge           

The site sedimentation dam was to be desludged to maintain its operational capacity.  During the planning phase, the pH and the turbidity were found to exceed the licence limits and required treatment prior to discharge. 

The client wished to move away from the traditional manual addition of chemicals & overnight settling approach, due to inconsistencies in treatment performance and WHS concerns with chemical handling.

Our Solution
Aquatic Engineering were engaged to treat and remove the water prior to the mechanical desludging.
AEA’s Trident 1 (T1) is a complete water treatment system featuring:
•    pH correction
•    integrated flocculation tank
•    chemical dosing
•    lamella clarifier
•    discharge monitoring

The Trident1 was set up adjacent to the dam and water was processed through the unit, using AEA 413 coagulant and AEA 111 flocculant.  
 

For proof of performance, the treated water was initially returned to the dam, with pH, turbidity and flowrate were monitored via the Trident 1’s instrumentation.  The unit was configured that if pH or turbidity alarms were triggered, a signal was sent to stop the feed pump.
 

The pH and turbidity levels were confirmed by a NATA laboratory, then automated continuous discharge began until the dam was empty.
 

AEA’s Trident 1 ability to automatically treat and monitor the water met the client’s requirements, with no environmental or WHS incidents and allowed the desludging program to continue.