Discharge - ADCP comparison

General:

To our knowledge, ADCPs are currently offered by only three companies: Ott, SonTek and RDI/Teledyne. Whereas Ott uses Nortek-sensors and fits them into their system, SonTek and RDI include produce their own sensors.

An ADCP-system consists of

the sensor - which does the actual measurements
the platform - a small board or raft on which the sensor is mounted (can be omitted if the ADCP is to be operated from an ordinary boat)
the communication unit - ensures the data transfer between the control unit and the sensor
control unit - usually a laptop or PDA with special software
GPS-system - optional, may include dGPS base station

SonTek and RDI/Teledyne let you combine these components more or less freely; for Ott, the system is premanufactured and cannot be altered by the user.

Things to consider:

intended range of river depths: The sensors differ considerably in their range. Especially measuring shallow flow can be problematic.
platform: Do you want to operate the ADCP from a small tethered boat, remotely controlled boat, an ordinary one or be flexible?
bottom tracking vs. GPS: bottom tracking determines the sensors position RELATIVE to the river bed (precise and fast; problematic with great depths or moving bed). GPS uses satellites for getting ABSOLUTE positions (no problem with moving beds; GPS reception is often poor down in the valley)
GPS, dGPS, GNSS, RTK: What is sold as "dGPS" is often only a SBAS-corrected GPS (only rover, no base). dGPS with postprocessing may not be possible. RTK provides high real time accuracy, but requires a base station. Systems supporting other positioning standards (GLONASS, Galileo) may provide better fix in marginal locations.
integration of existing equipment (PDA, GPS): May not be easily possible, make sure.

Sensor:

Name

company

# transducers

frequency

Sensor blanking

minimum water depth

maximum water depth

velocity range

max no of cells

accuracy

Bottom tracking

remarks

price

date

(m)

(relative)

Qliner

OTT

3?

2 MHz

0.35

10

+/- 10 m/s

40

1 %

no

includes vertical beam, 2d only

18100.00

Sep 2013 (Germany)

1 MHz

0.45

20

40

vertical methods

RiverSurveyor S5/M9

SonTek

5

S5: 5 Sensoren (3 MHz)

0.06

0,3

5 (15)

+/- 20 m/s

128

up to 0,25 %

yes

variable cell size

16000.00

Sep 2013 (Germany)

9

M9: 9 Sensoren (3 + 1 MHz)

0.06

0,3

40 (80)

27200.00

Sep 2013 (Germany)

using BT (GPS)

River Cat

SonTek

5/3/1,5 MHz

2/3/10

0,25/0,5/0,8

+/- 10 m/s

?

0,1 cm/s

yes

up to 100 cells

no longer available

Rio Grande Workhorse

Teledyne RDI

4

1.2 MHz

0.05

0.6 (0.5)

25 (30)

+/- 20 m/s

128/255

0,25 %

yes

128 cells

35300.00

Aug 2013 (Germany)

0.6 MHz

0.25

0.7

80

128/255

RiverRay

Teledyne RDI

4+1

0.6 MHz

0.6 (0.4)

40 (60)

+/- 20 m/s

200

up to 0,25 %

yes

includes vertical beam as of new

38700.00

Aug 2013 (Germany)

80 for z only

Stream Pro

Teledyne RDI

?

2 MHz

0,1

6

+/- 5 m/s

30

1 %

yes

30 cells

33300.00

Aug 2013 (Germany)

(version with depth upgrade)

Platform:

Name	Company	fits sensor	replaceable by user	operation	shape	weight (empty/complete, kg)	size	price (€)	date
Riverboat	Oceanscience	Teledyne RDI Workhorse	yes	tethered	trimaran	7/14	121x81 cm	5700.00	Aug 2013 (Germany)
Riverboat ST	Oceanscience	SonTek RiverSurveyor S5 or M9	yes?	tethered	trimaran
StreamPro (standard)	RDInstruments	Teledyne RDI StreamPro	yes	tethered	trimaran	-/5	70x44x11 cm
Riverboat SP	Oceanscience	Teledyne RDI StreamPro	yes	tethered	trimaran		114cm x 81cm	4900.00	Aug 2013 (Germany)
High-Speed Riverboat	Oceanscience	SonTek and Teledyne RDI	yes?	tethered	trimaran	13.6	152x122 cm	8900.00	Jun 2011 (Germany)
Qliner	Ott	Ott/Nortek	no	tethered	catamaran
Hydroboard 0.91	Sontek	SonTek RiverSurveyor S5 or M9	?	tethered	board		91 cm	2400.00	Aug 2013 (Germany)
Hydroboard 1.19	Sontek	SonTek RiverSurveyor S5 or M9	?	tethered	board		119 cm	3200.00	Aug 2013 (Germany)
Q-Boat 1800P	Oceanscience	various	yes	remote	single hull	25/40	180cm x 89cm	21900.00	Sep 2013 (Germany)
Q-Boat 1800D	Oceanscience	various	yes	remote	single hull	25/40	180cm x 89cm	13600.00	Sep 2013 (Germany)
Q-Boat 1550T	Oceanscience	?	?	remote	trimaran
Workhorse	RDInstruments	Teledyne RDI	yes	tethered	trimaran	10/17	120x80x18 cm
Riverray	RDInstruments/Oceanscience	Teledyne RDI	yes	tethered	trimaran	10/17	120x80x18 cm
Torrent Board V4 standard	Sontek	SonTek RiverSurveyor S5 or M9	?	tethered	board	4.7/9.8	105x65 cmx25	3900.00	Aug 2013 (Germany)
Torrent Board V4 mini (SFF)	Sontek	SonTek RiverSurveyor S5 or M9	?	tethered	board	3.1/8.2	80x50x15 cm