Environmental Engineering Reference
In-Depth Information
Table 1.2
Summary of selected attributes of fi ve suspended-sediment surrogate technologies.
Digital optic
imaging
Pressure
difference
Technology
Turbidity (bulk optics)
Laser
Hydroacoustic
Multi-camera
stream-side
pumping
system
In situ
Double
Bubbler
In situ
single-frequency
acoustic Doppler
profi ler
In situ
multiple-
frequency
acoustic Doppler
profi ler
Instrument or
type
In situ
turbidimeter
In situ
OBS
In situ
LISST-100
Manually
deployed
LISST-SL
ca
. $5,000
(summer 2008)
About 1
About 5
About 6
About 1
-2
About 1
Price relative to
in situ
turbidimeter
×
×
×
×
×
×
About 2
×
-4
×
Unknown
0-10 g/l;
future
testing may
elucidate a
larger upper
limit
Larger than
about 10 g/L,
but needs
more
research;
theoretically
no upper limit
Signal attenuation
limited as
function of PSD
and frequency
Signal attenuation
limited as
function of PSD
and frequency
Approximate
concentration
measurement
range
Standard 0-2 g/L.
Available at
larger ranges
Standard 0-5 g/L.
Available at
larger ranges
Depending on
versions: 0-2 g/L
(particle size
dependent)
About 0-2 g/L
(particle size
dependent)
Approximate
measurement
range, PSD
(mm)
Does not measure
PSD
Does not measure
PSD
0.0025-0.5 or
0.00125-0.25
0.0025-0.5 or
0.00125-
0.25
0.004 - 4.0
Does not
measure PSD
Does not measure
PSD
Particle size
dependent.
Ratio circumference
to wavelength
May measure sand
versus silt/clay
content. Particle
size dependent.
Ratio circumference
to wavelength
1
1
<
<
