2.1.4.1 Observed data


2.1.4.1.1 Stage and streamflow data

There are 43 streamflow gauging stations (Bioregional Assessment Programme, Dataset 1) in the subregion: 39 are located in the Hunter river basin and have gauge IDs with the prefix 210---, and four are located in the Macquarie-Tuggerah lakes basin and have gauge IDs prefixed by 211--- (Figure 32). There are 34 and 14 gauging stations used for AWRA-R and AWRA-L surface water model calibrations, respectively. The site details and data used for surface water modelling are summarised in Table 8.

Table 8 Gauge information for streamflow data for the Hunter subregion

AWRA-R = Australian Water Resources Assessment river model

AWRA-L = Australian Water Resources Assessment landscape model


Gauge ID

River name

Gauge name

Catchment area

(km2)

Latitude

Longitude

Gauge opened

Gauge closed

AWRA module

210001

Hunter

Singleton

16,400

–32.562°

151.170°

3 Jan 1913

No

AWRA-R

210002

Hunter

Muswellbrook Br

4,220

–32.258°

150.888°

2 Jan 1913

No

AWRA-R

210004

Wollombi Brook

Warkworth

1,848

–32.572°

151.045°

10 Feb 1908

No

AWRA-R

210006

Goulburn

Coggan

3,340

–32.345°

150.102°

1 Jan 1913

No

AWRA-R

210011

Williams

Tillegra

194

–32.320°

151.687°

20 Feb1931

No

AWRA-L

210014

Rouchel Brook

Rouchel Brook (The Vale)

395

–32.153°

151.048°

7 Dec 1934

No

AWRA-R

AWRA-L

210015

Hunter

Glenbawn

1,295

–32.113°

150.990°

1 Dec 1940

No

AWRA-R

210016

Goulburn

Kerrabee

4,950

–32.418°

150.318°

15 Dec 1940

No

AWRA-R

210017

Moonan Brook

Moonan Brook

103

–31.943°

151.280°

18 Dec 1940

No

AWRA-L

210022

Allyn

Halton

205

–32.308°

151.512°

12 Dec 1940

No

AWRA-L

210028

Wollombi Brook

Wollombi Brook at Bulga

1,672

–32.651°

151.020°

27 Dec 1949

No

AWRA-R

210031

Goulburn

Sandy Hollow

6,810

–32.347°

150.573°

24 Dec 1954

No

AWRA-R

210040

Wybong Ck

Wybong

676

–32.270°

150.635°

16 Dec 1955

No

AWRA-R

AWRA-L

210042

Foy Brook

Ravensworth

170

–32.398°

151.047°

24 Dec 1956

No

AWRA-R

210044

Glennies Ck

Middle Falbrook (Fal Dam Site)

466

–32.452°

151.148°

27 Jan 1956

No

AWRA-R

210048

Wollombi Brook

Paynes Crossing

1,064

–32.860°

151.058°

2 Dec 1940

No

AWRA-L

210052

Pages

Gundy Recorder

1,050

–32.012°

150.997°

26 De 1958

No

AWRA-R

AWRA-L

210055

Hunter

Denman

4,530

–32.382°

150.710°

5 Feb 1959

No

AWRA-R

210056

Hunter

Aberdeen

3,090

–32.160°

150.882°

18 De 1959

No

AWRA-R

210059

Bayswater Ck

D/S Liddell (Site 2)

88

–32.403°

151.022°

3 Dec 1973

No

AWRA-R

210060

Baerami Ck

Baerami

384

–32.445°

150.452°

15 Dec 1980

1 Jan 1992

AWRA-R

210061

Pages

Blandford (Bickham)

302

–31.812°

150.925°

21 Dec 1960

No

AWRA-R

210064

Hunter

Greta

17,320

–32.667°

151.400°

6 Dec 1968

No

AWRA-R

210080

West Brook

U/S Glendon Brook

80

–32.473°

151.282°

30 Dec 1969

No

AWRA-R AWRA-L

210082

Wollar Ck

U/S Goulburn

274

–32.340°

149.952°

1 Dec 1980

1 Jan 1997

AWRA-R

210083

Hunter

Liddell

13,400

–32.490°

150.922°

6 Dec 1969

No

AWRA-R

210084

Glennies Ck

The Rocks No.2

227

–32.365°

151.238°

6 Dec 1969

No

AWRA-R

210087

Doyles Ck

Doyles Ck

202

–32.513°

150.798°

2 Jan 1987

No

AWRA-R

210088

Dart Brook

Dart Brook at Aberdeen No. 2

799

–32.174°

150.868°

21 Dec 1970

No

AWRA-R

210089

Black Creek

Black Creek at Rothbury

220

–32.717°

151.326°

31 Dec 1972

No

AWRA-R

210093

Kingdon Ponds Ck

Nr. Parkville

177

–31.958°

150.855°

3 Dec 1972

No

AWRA-R AWRA-L

210120

Apple Tree Ck

Dural Gap

29

–32.562°

150.847°

14 Dec 1984

1 Jan 1998

AWRA-R

210123

Fal Brook

U/S Glennies Ck Dam

106

–32.288°

151.265°

27 Dec 1989

No

AWRA-L

210124

Dart Brook

Yarrandi Br

233

–32.013°

150.782°

10 Dec 1994

No

AWRA-R

210127

Hunter

U/S Glennies Ck

13,855

–32.502°

151.060°

25 Dec 1993

No

AWRA-R

210128

Hunter

Mason Dieu

14,394

–32.533°

151.048°

27 Dec 1993

No

AWRA-R

210131

Black Ck

D/S Anvil Ck

155

–32.052°

151.033°

29 Dec 1993

No

AWRA-R

210134

Hunter

Long Point

16310

–32.562°

151.137°

29 Dec 1993

No

AWRA-R

210135

Wollombi Brook

D/S Brickmans Br

1088

–32.850°

151.058°

18 Dec 1995

No

AWRA-R

211008

Jigadee Ck

Avondale

55

–33.067°

151.467°

19 Dec 1969

No

AWRA-L

211009

Wyong

Gracemere

236

–33.272°

151.360°

26 Dec 1972

No

AWRA-L

211010

Jilliby Ck

U/S Wyong R (Durren La)

92

–33.248°

151.390°

21 Dec 1972

No

AWRA-L

211013

Ourimbah Ck

U/S Weir

83

–33.348°

151.343°

14 Dec 1976

No

AWRA-L

Data: Bioregional Assessment Programme (Dataset 1)

Figure 32

Figure 32 Location of stream gauges in the Hunter subregion (listed in Table 8)

Data: Bioregional Assessment Programme (Dataset 1, Dataset 15), Bureau of Meteorology (Dataset 14)

The daily streamflow values in the time series are aggregated from instantaneous observations of streamflow that have been converted from observed stage height using a rating curve. Thus the quality of the streamflow records depend on the quality of the rating curves.

Using the numerical quality codes that are part of the streamflow data records, the daily streamflow data were processed into unified six-class quality codes for each gauge (Viney et al., 2011; Zhang et al., 2013) (Table 9). The six unified quality categories are defined as follows:

  • good: data are an accurate representation of streamflow
  • fair: data are a moderately accurate representation of streamflow
  • poor: data are a poor representation of streamflow and may be unsuitable for some quantitative applications
  • unverified: data quality is not known
  • non-conforming: data are unsuitable for most applications requiring quantitative analysis, but may contain useful qualitative information
  • missing: data are missing or unusable.

Streamflow data flagged as good, fair, poor or unverified were kept while the flow data flagged as non-conforming were excluded. The non-conforming and missing streamflow data are both labelled in the dataset as –9999.

Table 9 Quality codes for the NSW gauges for the Hunter subregion


Numerical codes

Description

<17, 30, 32–34, 36–39, 94

Good

17, 31, 40–46, 57–58, 82, 95

Fair

26, 51, 54, 60–75, 80, 91, 100,140

Poor

130

Unverified

35, 52, 77, 152

Non-conforming

153–255

Missing

Data: Bioregional Assessment Programme (Dataset 1)

Figure 33 summarises the percentage of each quality code for each streamflow gauge. No streamflow gauges have non-conforming data. Most of the data falls into the categories of ‘good’, ‘fair’ and ‘unverified’. The amount of missing data for eight catchments accounts for more than 30%.

Figure 33

Figure 33 Percentage of streamflow data in each quality code class by gauging station

Data: Bioregional Assessment Programme (Dataset 1)

The stage and streamflow data are used as provided in the calibration of surface water models reported in companion product 2.6.1 for the Hunter subregion (Zhang et al., 2018).

2.1.4.1.2 River cross-sections

Information on stream cross-sections are used in AWRA-R to represent the geometry of a river reach. A river reach is defined for modelling purposes as the runoff contributing area between two streamflow gauges or simulation nodes. This definition expands on the more traditional definition of a reach, which includes only the segment of river between two streamflow gauges or simulation nodes. Reach geometry – as defined by the upstream and downstream cross-sections – is used in AWRA-R to compute instream actual evapotranspiration and rainfall fluxes, instream capacity and losses to groundwater (Lerat et al., 2013; Dutta et al., 2014). The cross-sections for 34 streamflow gauges used in AWRA-R (Table 8) were obtained from CSIRO (Dataset 2). These, plus the 22 headwater derived cross-sections (see Section 2.1.4.2.1), defined the calibration node-link network (CSIRO Land and Water, Dataset 7), where a link is defined as the element that routes water through the system.

DPI Water collects cross-section data every few years. In AWRA-R, only the latest or most detailed (for example, the one with more distance measurements) was used, hence potential changes in cross-section due to scour and re-deposition of sediment after peak flows are not reflected in the model (McMillan et al., 2010). In addition, distances between gauges vary from a few to tens of kilometres, which may result in an underestimation or overestimation of the river width and depth when averaging the river instream capacity from the upstream and downstream cross-sections. Model calibration will partially compensate proportional biases arising from this underestimation.

Last updated:
18 January 2019
Thumbnail of the Hunter subregion

Product Finalisation date

2018

ASSESSMENT