The Membrane Concentrate Pilot Wetland Project is being conducted by the City of Oxnard Water Division to
assist with the City's water resources master planning process and implementation of the Groundwater Recovery
Enhancement And Treatment (GREAT) Program. Proposed water production technologies will generate brine
concentrate that will require disposal. One conceptual alternative could be to use the membrane concentrate as a
water source to brackish or salt marsh wetlands.
CH2M HILL is conducting the Membrane Concentrate Pilot Wetlands Project to determine if membrane
concentrate could be used for regional benefit, including assisting with restoration of the Ormond Beach wetlands
system. The project consists of twelve 1.1 m2 wetland tanks comprised of six wetland types and two replicates.
The pilot wetlands include a water storage tank, constant head tank, and all associated piping. The wetland types
include five flow-through mesocosms (surface flow (SF) high marsh, SF low marsh, horizontal subsurface flow
(SSF), peat-based vertical upflow (VF), and submerged aquatic vegetation (SAV)), and a saltgrass evaporation
system. The evaporation cells receive concentrate inflow, but are operated to achieve a zero discharge.
Of the wetland types selected, the SF high marsh, SF low marsh, and the SAV cells represent the major brackish
water plant communities known to exist within the existing Ormond Beach wetlands. Plants were obtained from
native plant nurseries. The primary water source is reverse osmosis (RO) membrane concentrate from the Port Hueneme Water
Authority's Brackish Water Research Desalination Facility.
Preliminary data available from project Phases reported in this paper indicate the following:
native wetland plants adapted to salt and brackish water conditions exhibited normal, even vigorous growth;
parameters of greatest concern such as selenium and nitrate-nitrogen significantly decreased to environmentally
safe levels within the wetland, mostly in the VF and SFLM wetlands;
concentrations of many inorganic water quality parameters did not decline during the study, but some, such as
calcium, alkalinity, and total hardness declined in the SAV wetlands; and,
treatment by the marshes in general yielded a brackish water with significantly reduced contaminant levels
that, with further testing and regulatory approval, may be used for regional benefit, including assisting with restoration of regional estuarine wetlands. Includes 8 references, tables, figure.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 430 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 11 |
| Published : | 03/01/2005 |
