Territory Stories

Alice Springs Flood Investigation and Floodplian Mapping Study

Details:

Title

Alice Springs Flood Investigation and Floodplian Mapping Study

Creator

WRM Water & Environment Pty Ltd; Northern Territory. Department of Lands, Planning & the Environment

Editor

Roads, Greg

Collection

E-Publications; PublicationNT; E-Books; EXTA1463

Date

2015-10-12

Location

Alice Springs

Description

Made available via the Publications (Legal Deposit) Act 2004 (NT).; WRM Water & Environment (WRM) was commissioned by the Department of Lands & Planning (DLP) to undertake a flood study of the Todd River in the Alice Springs area. The aim of the study is to develop a 2 dimensional flood model, which allows flood flow in a complex flood plain to be modelled, to determine the extent and severity of riverine flooding in the town of Alice Springs and the Alice Springs rural area south of Heavitree Gap. The purpose of the study is to produce floodplain maps of the Alice Springs and its rural area for land use planning and counter – disaster purposes. This study is an extension of the Alice Springs Farms Area Floodplain Mapping Study (WRM, 2006), undertaken by WRM on behalf of the Department of Planning & Infrastructure in 2006 in order to develop detailed Todd River floodplain maps for the rural area south of Alice Springs.

Table of contents

1. INTRODUCTION -- 2. CATCHMENT DESCRIPTION -- 3. AVAILABLE DATA -- 4. CALIBRATION AND AND VERIFICATION EVENTS -- 5. HYDROLOGIC MODEL CALIBRATION AND VERIFICATION -- 6. HYDRAULIC MODEL DEVELOPMENTLOPMENT -- 7. HYDRAULIC MODEL CALIBRATION -- 8. FLOOD FREQUENCY ANALYSIS -- 9. DESIGN EVENT HYDROLOY -- 10. DESIGN FLOOD LEVELS AND EXTENTS -- 11. CONCLUSION -- 12. REFERENCES

Language

English

Subject

Flood control -- Northern Territory -- Alice Springs; Flood damage prevention -- Northern Territory -- Alice Springs; Floodplain management -- Northern Territory -- Alice Springs; Alice Springs Flood Investigation; Floodplain Mapping

Publisher name

WRM Water & Environment Pty Ltd

Place of publication

Darwin (N.T.)

Series

EXTA1463

Format

vii, 95 pages : colour maps ; 30 cm.

File type

application/pdf.

Copyright owner

Check within Publication or with content Publisher.

Parent handle

https://hdl.handle.net/10070/259732

Citation address

https://hdl.handle.net/10070/494349

Page content

0269-02-C1 12 October 2015 15 however only one gauging has been made for a discharge of greater than 50 m3/s. The highest gauged discharge (51.5m3/s) was recorded in March 1972. Figure 3.3 shows the adopted rating curve and recorded gaugings for the Big Dipper stream gauging station. The quality codes attached to the NRETAS rating curve for the Big Dipper gauging station indicate that the rating curve is satisfactory for discharges up to 513m3/s. It is noted that the highest recorded flood level during the period of record (January 1974 flood) is within the rated range. Based on the available data the NRETAS rating curve for the Big Dipper gauging station has been adopted for use in this study without modification. Figure 3.3 Stage-Discharge Curve adopted at Big Dipper, Charles River (G0060047) 3.4.4 Todd River at Anzac Oval/Wills Terrace (G0060009) The recording of water levels at Wills Terrace station commenced in 1952. This station was relocated to the Anzac Oval location in April 1970. The current station is about 250m upstream of the original station. At these stations, a combined total of 98 gaugings for discharges greater that 10 m3/s have been made, and 24 gaugings for discharges greater than 100m3/s. The highest gauged discharge at Anzac Oval/Wills Terrace stations (450 m3/s) was recorded in March 1972. It is noted that the low flow gaugings prior to 1972 that were related to the Wills Terrace gauge have been removed from Figure 3.4. The Anzac Oval high flow rating curve was also updated in 1996, after a comprehensive review undertaken as part of the Todd River flood studies (GHD, 1996). The updated rating curve has been used in GHD (1996) and GHD (2001). Again, for all practical purposes, the rating curve provided by NRETA appears to be the same as the GHD (1996) curve. It is believed that NRETA may have fine tuned the high flow rating curve using data from the 1996 study. Although the Anzac Oval gauging station has been rated up to a discharge of 1500m3/s, NRETAS have expressed concerns regarding the accuracy of the rating curve at high discharges