FoSBR

Friends of Sandy Bay Rivulet Inc.

Newsletter 10 — Nov/Dec 2008

OFFICE BEARERS:

Next Meeting : Rivulet Visit — Now & Then President James Bowler Secretary Julia Greenhill A joint meeting in conjunction with the Sandy Bay Historical Society on Treasurer Beth Harnett Sunday 23rd November 2008. The meeting will commence at 12.30 with Committee Patsy Jones a sausage sizzle. Venue is Waterworks Reserve Site 1. As usual bring Deb Maeder your own food, drinks, etc. Photos of various aspects of the rivulet will Penny Parrish be on display. Public Officer Julia Greenhill Commencing about 1.30pm, after the sausage sizzle, we will visit various sites along the rivulet. Jim Bowler & Penny Parrish will lead the discussion and commentary but other input will be welcomed. It is Fauna Watch - intended to cover some of the fascinating history and natural history of “Scats, Tracks and a the rivulet. In case the Tasmanian weather is its normal variable self we Bird or Ten” aim to travel between key points along the rivulet by car. On Sunday 12th October at the Waterworks a select group met Editorial to learn something about fauna watch. Leading the group’s en- The Executive lodged a representa- the members of the City Council clearly deavors were Dr Obendorf, Don tion with the HCC concerning the demonstrated its lack of understanding of Knowler and Sonya Stallbaum proposed development at 9 –11 Lin- the scientific issues involved. (HCC) coln St. The work proposed included the demolition of an old two flat One has to ask why we have these provi- The meeting was aimed at en- building and the construction of two sions if they are not to be applied? The couraging a wider knowledge of new flats and a vehicle turning circle. answer can only be a lack of appreciation the fauna of our area, and in- of the factors involved. There is obvi- cluded some bird identification. Our action was taken with reluctance ously a need to improve the understand- as some aspects of the proposal were ing of the professionals involved in the It is hoped that in the long term laudable and we also prefer to foster analysis and the Aldermen who make the we will have a better and more a good working relationship with final decisions. substantive record of fauna in landowners. Our concern was the impact of the development on the the rivulet riparian zone and sur- As a result we intend, in the future, fea- rounds. riparian zone and the rivulet. turing specialist articles on the rivulet Riparian zones are not necessary just and about the current status of water This will help both in the protec- for recreational purposes, but to es- sensitive urban design and riparian zone tion of our native species and in tablish and maintain the rivulet as a practice. Hopefully this, coupled with a our capacity to make better deci- aquatic and terrestrial habitat , as a wider distribution, will help get the mes- sions on land use. wildlife corridor and as a means of sage across so the decision makers can controlling the volume and quality of start making informed and reasoned deci- Thanks to all who participated surface and sub surface run off. The sions. zone is also important in reducing We acknowledge and thank the bank erosion and stream sedimenta- following organisations for their tion. The issue is extremely complex. support: The 10m width in the Planning SHIPPIES Scheme was adopted by the HCC on Shipwrights Arms Hotel the basis of minimum national rec- 29 Trumpeter St, Battery Point ommendations. Unfortunately in the Planning Scheme there are discre- CITY COUNCIL tionary clauses which are often ap- Town Hall, Hobart plied without understanding the real issues involved in modern water sen- We also acknowledge the assistance sitive urban design nor the role or provided by the Office of Senator function of riparian zones. Sadly in Eric Abetz in the production of this assessing the proposal a majority of Newsletter COMMENTS ON THE SANDY two species in very low abundance, in protect, maintain and perhaps restore neighbouring streams to the south. The only aspects of its urban streams, both in BAY RIVULET streams which approach the aquatic ecologi- amenity and intrinsic ecosystems, then cal state of Sandy Bay Rivulet are Browns implementation of the 10 m setback, By Dr Peter Davies River and New Town Rivulet on the western coupled with requirements for active (A document prepared in relation to the shore of the greater Hobart-Glenorchy- management/improvement (weed con- proposed development at 9—11 Lincoln St) Kingborough area, and the lowest reaches of trol, stabilisation, vegetation planting Risdon Brook on the urban western shore of etc) should be a minimum requirement Background the Derwent estuary. This document is a commentary on the recent The Proposed Development Hobart City Council decision to approve a Along with fish populations, there is an abundant and diverse freshwater inverte- I am particularly concerned that new development application at 9-11 Lincoln developments are allowed to encroach brate fauna in Sandy Bay Rivulet, and ob- Street, Sandy Bay, Hobart. The nature of the within the 10 m setback from streams servations of resident platypus and native comments relates to the need for a 10 m set- required under Clause D.6.1 of the Plan- water rats. back and the aquatic environmental values of ning Scheme. Clause D.6.2 gives dis- the adjacent stream, Sandy Bay Rivulet. cretion to vary the setback where it can While the stream catchment is urbanised in be demonstrated that: I have been a professional aquatic scientist its middle and lower reaches, and it suffers for 28 years, working in and from water abstraction, urban runoff and in a) there will be minimum adverse im- throughout . I am a Research Fellow stream structures (that partially impede fish pact upon the environment; movement), the stream has a high level of at the University of Tasmania, member of the b) no compromising of recreational aquatic biodiversity. A chief reason for this Forest Practices Authority Board, and Chair opportunities; of the Murray Darling Basin’s Sustainable is the predominance of vegetation along its Rivers Audit. banks and the absence of significant chronic c) there will be no increased risk of any and/or acute water pollution. hazard such as flooding, erosion or land The stream instability level; and Sandy Bay Rivulet, in my professional I have been monitoring the status of the d) there will be no constraint on access opinion, is a stream which warrants ongoing to a Council or other utility service. aquatic fauna of Sandy Bay Rivulet for over management with the aim of protecting and a decade. This has consisted of periodic sur- sustaining its natural values. It has the op- The proposed development has a 5 veys of fish, aquatic invertebrates, and obser- portunity to be a centrepiece of environ- metre setback which is encroached upon vations of aquatic habitat. I have also been mental rehabilitation and protection in the in part by decks. involved in the installation of structures to Hobart municipality. restore fish passage in three of the main in stream culverts in the Rivulet. This reach of the Sandy Bay Rivulet Stream management between Regent Street and Sandy Bay Sandy Bay Rivulet contains an unusually Clause D.6.1 of the Planning Scheme re- Road contains the majority of the popu- abundant native fish fauna for a suburban quires a setback for any development of 10 lation of both the jollytail and freshwa- stream. This fauna is dominated by four na- metres from the top of the bank of any open ter flathead. For this reason alone, I tive fish species: the Jollytail (Galaxias watercourse. This has the potential to would be concerned if any new develop- maculatus), the mountain galaxias (Galaxias achieve several aims relating to protection ments do not demonstrably protect truttaceus), the freshwater flathead or sandy of assets from flood damage, coupled with and/or improve the habitat values of the (Pseudaphritis urvillii) and the shortfin eel opportunities for protection and improve- stream by: (Anguilla australis). Only one exotic species, ment of riparian (bank side) land and vege- Incorporating a true 10 m setback brown trout (Salmo trutta), has been recorded tation, and hence aquatic biodiversity val- • and is present in several pools. The majority ues. for the entire length of the proposed of the population of both Jollytail and fresh- development along the stream; water flathead is found between Regent Riparian zones provide key roles for stream • Including appropriate plantings, Street and Sandy Bay Road, while the upper ecosystems, including shading, bank stabili- weed control, bank stabilisation in the reaches are dominated by mountain galaxias sation; habitat for platypus, water rats, adult setback within the development pro- and eels. aquatic insects, and birds; control of surface sediment inputs to streams. In addition the posal. vegetation provides a key food resource for The size and diversity of this fish commu- Ensuring no new or ongoing dis- the stream biota – leaf and other litter. This • nity is unique in the greater Hobart municipal ruption or disturbance to the riparian area. contains brown trout but forms the basis of the food chain which also supports fish and platypus. area and/or the area of the stream chan- no resident native fish, and native fish are nel (e.g. through surface runoff, inap- present only occasionally, and as only one or propriate access or structures). If the aim of the Hobart City Council is to

Galaxias maculatus (Jollytail) Graham Edgar Galaxias truttaceus (Mountain) Graham Edgar