Sludge Watch ==> Orange County - sewage effluent into drinking supply

[Maureen Reilly]

Sludgewatch Admin:

Orange County California is planning to run its sewage treatment plant 
effluent through a membrane filter and then run it into the drinking water 
supply aquifer.

Why is this a concern?

If the issues associated with 'toilet to tap' aren't obvious enough, 
contemplate the more alarming 'hospital to tap', insecticide to tap', 
'laboratory to tap', 'pharmacy to tap', ...etc.

There are issues as to water quality especially during storm surges or power 
failures.
There are issues because the contamination sources into sewage treatment 
plants are so many and so varied that it is impossible to say on any given 
day what contaminants will be in the plant.

Extreme weather events are more common and can overwhelm urban 
infrastructure.

Hormones, pharmaceuticals, surfactants, cleansers, fire retardants, musks, 
antibiotic resistant pathogens, endocrine disruptors and personal use 
products end up in the treated water that comes out of sewage treatment 
plants.  These contaminants have environmental impacts in micro dosages.
You don't want to add to your toxic body burden by ingesting them.

This plan will create two water markets...those who can afford to bring 
bottled water into their household for drinking purposes and those who 
cannot afford to buy clean water for household beverages.

The wastewater industry is notoriously unaccountable to its sewage sludge 
victims...refusing for decades to investigate the many allegations of 
serious health impairments and deaths.  Why would we expect them to be frank 
and accountable for illnesses related to drinking sewage treatment plant 
effluent?

...........................................................



Orange County Water District (OCWD)

Orange County imports approximately 25% of its water supply from the 
Colorado River and Northern California. The remaining supply is drawn from 
groundwater. Currently, OCWD reclaims about 57,000 m3/day or 12.5 mgd of 
good quality water from secondary effluent to recharge the groundwater near 
to the coast to prevent seawater intrusion. The secondary effluent is 
therefore a source of water in the area.


Flow diversion of Santa Ana River for
groundwater recharge (flow is mostly treated wastewater
effluent from upstream during dry seasons)


One of the groundwater recharge basins


Future Sources of Water
To address the long term shortfall and to have reliable water supply, Orange 
County is implementing the Groundwater Replenishment System (GWRS). This is 
a large scale extension of their Water Factory 21 Project which successfully 
demonstrated the reliability of dual membrane technology in reclaiming water 
from secondary sewage effluent for injection into the groundwater to protect 
their potable water supply from seawater intrusion.

In GWRS, secondary treated wastewater effluent will be reclaimed using the 
latest and proven membrane technology of microfiltration and reverse osmosis 
(RO). This will produce good quality water which will then be used to 
replenish the existing groundwater source.

Benefits of GWRS
Besides meeting the long term water demand in Orange County, the GWRS would 
reduce wastewater effluent discharge into the sea and protect the beaches. 
It would avoid the need for a sea outfall which is not acceptable to the 
community. Furthermore, Orange County found that the GWRS was the cheaper 
option.

Because of the low salinity of the reclaimed water, the GWRS would also help 
to control the build-up of salinity in the groundwater caused by seawater 
intrusion as a result of excessive abstraction. It would also minimise the 
need for imported water from the Colorado River which has high salinity (as 
high as 1,600 ppm). Membrane technology has proven to be more reliable in 
producing good quality water. The reclaimed water is of better quality than 
current sources from the Colorado River and Santa Ana River.

Furthermore, the GWRS would obviate the need to transport water by pumping 
over long distances from Northern California and Colorado River.

More importantly, the GWRS would provide Orange County with a robust and 
reliable water supply to meet increasing water demand and help to diversify 
its water sources. The GWRS source is also drought-proof.

http://www.pub.gov.sg/NEWater_files/overseas_experiences/mapus_orange.html