Download Water Quality Analysis Standards

USWP Water Quality Analysis Standards
TEST
What It
Measures
Excellent
Good
Fair
Poor
Source
Dissolved
Oxygen (%
saturation)
pH
Amount of
oxygen in the
water
Acid/base of
water
80-120
70-80
120-140
50-70
>140
<50
7.0-7.5
6.5-7.0
7.5-8.5
5.5-6.5
8.5-9.0
<5.5
>9.0
Total
Phosphate
(mg/l)
Nitrate
(mg/l)
0-0.2
0.2-0.5
0.5-2.0
>2.0
0-3
3-5
5-10
>10
Chloride
(mg/l)
A salt of
phosphoric
acid
Amount of
nutrients in the
water
Amount of salt
in the water
Wind
Running
water
Acid rain
Industrial
pollution
Chemical spills
Detergents
0-20
20-50
50-250
>250
Alkalinity
ppm
(mg/l)
Buffering
capacity of
water
>200ppm or
mg/l
100-200ppm
or mg/l
20-100ppm
or mg/l
<20ppm or
mg/l
Turbidity
(NTU)
(feet)
Clearness of
the water
0-5 NTU
>4 ft
5-20 NTU
1-4 ft
20-70 NTU
4 inches-1ft
>70NTU
< 4inches
Temperature
(⁰C)
Amount of
average heat
Total
Dissolved
Solids (TDS)
(mg/l)
Combined
content of all
organic and
inorganic
substances
0-100
100-250
250-500
Generally
>27⁰C
>24⁰C for
trout
streams
>500
Biochemical
Oxygen
Demand
(BOD)
(mg/l)
amount of
dissolved
oxygen needed
by aerobic
biological
organisms
0-2
2-4
4-10
>10
Sewage
Fertilizer
Animal waste
Road salt
Water
treatment
plants
Pool water
Carbonate
bicarbonate
hydroxides in
soil, rocks
Sediment
Excessive
algae growth
Storms
Boat traffic
Waste heat
Solar heat
agricultural
and
residential
runoff,
leaching of
soil
contamination
Wastewater
treatment
plants