Recycling Treated Municipal Wastewater for Industrial Water Use

Section 2
Implementation Considerations
Craddock Consulting Engineers 2-3
In Association with CDM & James Crook
TM1-Sec2_0707.doc
Table 2.1. 2000 California Water Recycling Criteria
Type of Use
Irrigation of fodder, fiber, and seed crops, orchards b and
vineyards b , processed food crops c , nonfood-bearing
trees, ornamental nursery stock d , and sod farms d ;
flushing sanitary sewers
Irrigation of pasture for milking animals, landscape
areas e , ornamental nursery stock and sod farms where
public access is not restricted; landscape impoundments;
industrial or commercial cooling water where no mist is
created; nonstructural fire fighting; industrial boiler
feed; soil compaction; dust control; cleaning roads,
sidewalks, and outdoor areas
Irrigation of food crops b ; restricted recreational
impoundments; fish hatcheries
Irrigation of food crops f and open access landscape
areas g ; toilet and urinal flushing; industrial process
water; decorative fountains; commercial laundries and
car washes; snow-making; structural fire fighting;
industrial or commercial cooling where mist is created
Nonrestricted recreational impoundments
Total Coliform
Limits a
Treatment
Required
None required Oxidation
≤23/100 ml a
≤240/100 ml in more than
one sample in any 30-day
≤2.2/100 ml a
≤23/100 ml in more than one
sample in any 30-day period
≤2.2/100 ml a
≤23/100 ml in more than one
sample in any 30-day period
240/100 ml (maximum)
≤2.2/100 ml a
≤23/100 ml in more than one
sample in any 30-day period
240/100 ml (maximum)
Groundwater recharge by spreading Case-by-case evaluation
Oxidation
Disinfection
Oxidation
Disinfection
Oxidation
Coagulation h
Filtration i
Disinfection
Oxidation
Coagulation
Clarification j
Filtration i
Disinfection
Case-by-case
evaluation
a
Based on running 7-day median; daily sampling is required.
b
No contact between reclaimed water and edible portion of crop.
c
Food crops that undergo commercial pathogen-destroying prior to human consumption.
d
No irrigation for at least 14 days prior to harvesting, sale, or allowing public access.
e
Cemeteries, freeway landscaping, restricted access golf courses, and other controlled access areas.
f
Contact between reclaimed water and edible portion of crop; includes edible root crops.
g
Parks, playgrounds, schoolyards, residential landscaping, unrestricted access golf courses, and other
uncontrolled access irrigation areas.
h
Not required if the turbidity of influent to the filters is continuously measured, does not exceed 5 NTU
for more than 15 minutes and never exceeds 10 NTU, and there is capability to automatically activate
chemical addition or divert wastewater if the filter influent turbidity exceeds 5 NTU for more than 15
minutes.
i
The turbidity after filtration through filter media cannot exceed an average of 2 nephelometric turbidity
units (NTU) within any 24-hour period, 5 NTU more than 5 percent of the time within a 24-hour period,
and 10 NTU at any time. The turbidity after filtration through a membrane process cannot exceed 0.2
NTU more than 5 percent of the time within any 24-hour period and 0.5 NTU at any time.
j
Not required if reclaimed water is monitored for enteric viruses, Giardia, and Cryptosporidium.
Source: Adapted from State of California [2000a].