Catchment Health Indicator Program 2020 Supported by: In Partnership with: Written and produced by the following: Woo O’Reilly – Waterwatch Regional Facilitator Antia Brademann – Cooma Region Waterwatch Coordinator Martin Lind – Southern ACT Waterwatch Coordinator Bruno Ferronato – Ginninderra and Yass Region Waterwatch Coordinator Deb Kellock – Molonglo Waterwatch Coordinator Rod Ubrihien – Data Management The views and opinions expressed in this document do not necessarily reflect those of the ACT Government or Icon Water. For more information on the Upper Murrumbidgee Waterwatch program go to: http://www.act.waterwatch.org.au The Atlas of Living Australia provides database support to the Waterwatch program. Find all the local Waterwatch data at: https://biocollect.ala.org.au/actwaterwatch This document can be cited as: O’Reilly, W., Brademann, A., Ferronato, B., Kellock, D., Lind, M., and Ubrihien, R. (2021) Catchment Health Indicator Program: Report Card 2020. Upper Murrumbidgee Waterwatch, Canberra. All images are the property of Waterwatch unless otherwise stated: - Brindabella Venturers, page 6 and aerial of Bogong Creek, page 111 - J. Lehane. - Tiger snake at Chimney Creek, page 52 - N. Loades. - Volunteers at QAQC event, page 128 - M. Gardner. - Front cover of wet and dry McKellar Wetlands - L. Wensing. b Primrose Creek PRI1 69 Queanbeyan River QUE1 70 Contents Queanbeyan River QUE2 71 Executive Summary 2 Queanbeyan River QUE3 72 Introduction 4 Scabbing Flat Creek SCA1 73 Cooma Region Catchment Facts 8 Sullivans Creek SUL1 74 Badja River BAD1 10 Sullivans Creek ANU SUL3 75 Badja River BAD2 11 Watson Wetlands and Ponds WAT1 76 Bredbo River BRD1 12 Weston Creek WES1 77 Bredbo River BRD2 13 Woolshed Creek WOO1 78 Cooma Creek COO1 14 Yandyguinula Creek YAN1 79 Cooma Creek COO2 15 Yarralumla Creek YAR1 80 Cooma Creek COO3 16 Southern ACT Catchment Facts 82 Cooma Back Creek COB1 17 Barney’s Gully MMB1 84 Gungoandra Creek GUD1 18 Bogong Creek Catchment BOG1 85 Kybeyan River KYB1 19 Cooleman Ridge Dams RAN1 86 Michelago Creek MIC1 20 Cotter River COT1 87 Murrumbidgee River CMM1 21 Cotter River COT2 88 Murrumbidgee River CMM2 22 Cotter River COT3 89 Murrumbidgee River CMM3 23 Gibraltar Creek GIB1 90 Murrumbidgee River CMM5 25 Gudgenby River Catchment CGG1 91 Murrumbidgee River CMM6 26 Guises Creek Catchment GUI1 92 Numeralla River NUM1 27 Hospital Creek Catchment HOS1 93 Numeralla River NUM2 28 Isabella Pond ISA1 94 Numeralla River NUM3 29 Lake Tuggeranong Wetlands TLT1 95 Numeralla River NUM4 30 Lake Tuggeranong TLT2 96 Rock Flat Creek ROC1 31 Murrumbidgee River CMM7 97 Strike-A-Light River STR1 32 Murrumbidgee River CMM8 98 Ginninderra Catchment Facts 34 Murrumbidgee River CMM9 99 Ginninderra Creek GIN1 36 Murrumbidgee River CMM10 100 Ginninderra Creek GIN2 37 Naas River NAA1 101 Ginninderra Creek GIN3 38 Naas River NAA2 102 Ginninderra Creek GIN4 39 Orroral River ORR1 103 Ginninderra Creek GIN5 40 Paddy’s River Catchment PAD1 104 Ginninderra Creek GIN6 41 Point Hut Ponds MPG1 105 Gooromon Ponds Creek GOO1 42 Stranger Pond MSP11 106 Gungaderra Creek GDC1 43 Tidbinbilla River CTT1 107 Gungahlin Pond GUN2 44 Tuggeranong Creek, Upper TUG1 108 Kippax Creek KIP1 45 Tuggeranong Creek, Middle TUG2 109 McKellar Wetlands MCW1 46 Tuggeranong Creek, Lower TUG3 110 Mulligan’s Flat Dam MFL1 47 Yass Catchment Facts 112 Murrumbidgee River CMM11 48 Murrumbidgee River CMM12 114 The Valley Ponds GUN1 49 Murrumbidgee River CMM13 115 Yerrabi Pond YER1 50 Yass River YAS1 116 Molonglo Catchment Facts 52 Yass River YAS2 117 Banksia Street Wetland SUW2 54 Yass River YAS3 118 Burra Creek BUR1 55 Yass River YAS4 119 David Street Wetland SUW1 56 Special Fire Report 120 Dickson Wetland DIC1 57 Googong Creek GGG1 58 Platypus Month 124 Jerrabomberra Creek JER1 59 FrogWatch Highlights 128 Jerrabomberra Creek JER2 60 Volunteer list 130 Lyneham Wetland LYN1 61 Molonglo River MOL1 62 Glossary and Abbreviations 133 Molonglo River MOL2 63 Appendix I 134 Molonglo River MOL3 64 Molonglo River MOL4 65 Appendix II 136 Molonglo River MOL5 66 Appendix III 139 Molonglo River MOL6 67 Molonglo River MOL7 68 Appendix IV 141 1 Executive Summary Upper Murrumbidgee Waterwatch (Waterwatch) works with the community to monitor, raise awareness, educate, restore and protect our local waterways. Waterwatch has been running in the ACT region since 1995 and covers the Murrumbidgee catchment upstream of Burrinjuck Dam (with the exception of the Goodradigbee catchment). The total area monitored by Waterwatch is more than 11,400km2. Two primary functions of the Waterwatch program are to facilitate community engagement through the monitoring and care of local waterways, and to use the data (water quality, macroinvertebrate [waterbug] and riparian condition) as an early warning system for aquatic ecosystem health issues. A key output of this program is the annual Catchment Health Indicator Program (CHIP) report, which provides a numerical score of catchment health, displayed in individual reach (sections of waterway) report cards, using data collected by Waterwatch volunteers. The 2020 CHIP report is based upon 1,872 water quality surveys, 184 waterbug surveys and 219 riparian condition surveys conducted by over 200 volunteers. The total number of sites surveyed was 229 with a total of 98 reach report cards produced. Waterwatch now includes the important addition of the number of ‘dry’ surveys conducted in the overall survey tally (ie. when a volunteer has visited their site but it is completely dry). While these do not contribute to the CHIP score, they are an important factor in the condition of the catchment and highlight survey effort. A total of 50 water quality surveys were ‘dry’ in 2020 which is only one quarter of total in 2019. There were three new reaches created this year, all within the Southern ACT catchment. COT1 includes the upper Cotter River capturing the section above Corin Dam (complementing the two downstream reaches on the Cotter River), ORR1 takes in all of the Orroral River, which has been split away from the Gudgenby River reach, and NAA2 on the Naas River which is now split into two sections; one in the Namadgi National Park (NAA1) and a second downstream in the rural valley. Via a continual process of refinement and the addition of further sites as needed, the Waterwatch CHIP program ensures each year’s report best represents the condition of our catchment. Of the 98 reaches presented in this report (Table 1), four were scored as in excellent condition, two reaches in the Molonglo catchment plus two in Southern ACT. This was one more than 2019. A further 36 reaches were scored as being in good condition, which is one less than last year, and 55 reaches were in fair condition, two more than 2019. Four reaches received a poor score, one less than last year, and no reaches received a degraded score. While the range of scores did not change markedly from 2019, conditions influencing the scores most certainly did. Extended dry conditions could be attributed to many of the results in 2019, but in 2020, either a lack of rain, too much rain or, of course, bushfires, played a role. Table 1: CHIP results from 2020. CHIP Result Cooma Ginninderra Molonglo Southern ACT Yass Total Excellent (A) 0 0 2 2 0 4 Good (B) 11 3 10 12 0 36 Fair (C) 12 11 15 12 5 55 Poor (D) 0 1 0 1 1 3 Degraded (E) 0 0 0 0 0 0 2019 was the driest year on record. This followed on from a dry year in 2018. The adverse impacts this had on the catchment are well documented in previous CHIP reports. It was when the upper Murrumbidgee catchment was at its driest, however, that it was struck by bushfires in late 2019 and early 2020. Nearly the entire Badja River catchment and the headwaters of the Bredbo and Cowra Creek catchments were burnt due to the Badja Forest and Good Good fires which began in December 2019. Bushfires continued throughout January and February 2020 with 80% of Namadgi National Park and over a third of Kosciuszko National Park burned as well as impacting communities surrounding Tharwa, Bredbo and Numeralla. 2 Then the rain started. The timing had a devastating impact on our waterways in that much of the damage from the fire was already done and the heavy falls maximised the loss of ash, sand and soil from these fresh fire grounds. The first rains of 100mm+ in January sent the usually clear Badja River into a flow of thick, black mud as well as the lower Numeralla and Bredbo Rivers. Then when 60mm+ fell on southern ACT in mid-February, the Gudgenby, Paddy’s and Tidbinbilla rivers did the same. The rain washed ash and debris into the rivers and turbidity and phosphorus levels went beyond what most Waterwatch kits were capable of measuring. Thick layers of ash-laden mud lining the riverbanks and smothering the river substrate was, and still is, a feature of many of our major rivers including 120kms of the Murrumbidgee River from reaches CMM4-CMM13. More details on the impacts of the fires is available in a special fire report written by the University of Canberra using Waterwatch data on pages 120-124 of this report. The onset of heavy rain after the preceding dry years played out differently in non-fire affected parts of the catchment. Organic matter that had been building up in the landscape for years was suddenly flushed into rivers and wetlands. Urban reaches, such as in Cooma, Yass and Tuggeranong, detected high concentrations of phosphorus and/or nitrate washing out of gross pollutant traps and other unknown sources. Waterways adjacent to development sites experienced high turbidity. Waterways with simplified riparian corridors and poor in-stream vegetation are less able to process these influxes of material.