Skip Navigation Links.
Collapse Issue 561:<br />23 Jan 2023<br />_____________Issue 561:
23 Jan 2023
_____________
Collapse  NEWS NEWS
Draft flood plan proposes new minimum floor levels
Sammy Seal becomes ferry passenger
Meeting to discuss floodplain and council land plans
Working together 20 years later
Council may spend $133,000 on rare bushland project
Liberals select former councillor as election candidate
Nambus leaves Ettalong for Phillip Island
Taken to hospital
Family fun at Pearl Beach for Australia Day
Wednesday night bingo resumes
Sunny weather for a trip to Patonga
Men's Shed to consider conferring life membership
Bling It Up Gala to raise money for the Iris Foundation
Car boot sales return to Rogers Park
Donation for renovations to Umina CWA hall
Donation to youth cottage
Palm Beach ferry diverted
Rotary club prepares for year ahead
Body of missing bushwalker found at Patonga
Help with a tow
Events planned at Pearl Beach hall
Maritime-themed play area is open
RSL sub-branch to hold annual meeting
Call wildlife rescue for help with tangled birds
Month's rainfall is about average
Collapse  PLANNING PLANNING
Dual occupancy application resubmitted under new rules
Plan model is based on one flood event 35 years ago
Flood study tells of smaller extent and shallower depths
Flooding consultation is 'second round'
Collapse  FORUM FORUM
Good Samaritan helps a wild creature in need
Need for relief for the elderly at the bus stop
Wanting to walk, but where's the shade?
Do something before we have a fatality
Community is secondary without development foresight
'Low density' is not 94 people on two residential blocks
Collapse  HEALTH HEALTH
New Covid health management plan welcomed
New aged care executive appointed
Active virus numbers lowest in two months
Collapse  ARTS ARTS
Bush dance continues after 25 years
Troubadour expands its range of concerts and activities
Free mardi gras viewing party in Ettalong
Collapse  EDUCATION EDUCATION
Princess the pup is back
Parents raise $18,000 for school, with more to come
Bathroom upgrade for junior students
Bluey features on new basketball court
Students urged to take up training opportunities
List of items for Ettalong students
Start dates announced for Woy Woy campus
Uniform shop opens from Friday
Instructions for first day Year 7 students
Collapse  SPORT SPORT
Bunnies to return to senior competition?
Spot the rip
Boardriders seek member registrations before March
Grommet boardriders to hold registration day
Premier 'joins' Umina surf patrol
Bridge club trials Wednesday afternoon competition
Disabled surfers need volunteers for February event
Veteran bowlers surveyed on format preferences
Charity bowlers raise $1650
Umina United to hold junior grading
Eagles schedule pennant trials
Umina Rookies attend Central Coast challenge
Roosters to hold girls' meet and greet night

EXTRA!!!

[Download]

Plan model is based on one flood event 35 years ago

The Woy Woy Peninsula Floodplain Management Study has admitted its plan has been created "in the absence of any gauged water level or discharge data".

Instead, it is modelled on just one flood event 35 years ago using just 20 locations across the Peninsula and using rainfall data from Peats Ridge.

Despite the lack local rainfall, flood level or discharge data, the plan has not recommended that these be monitored.

The study said that "the parameters related to soil and groundwater were already calibrated against the long-term groundwater level observations".

"Calibration of the model in this study focused on parameters affecting surface water."

This was to be carried out against the estimated peak water depths from flooding events identified in a 2010 study.

Candidate events were in August 1972, May 1974, 1984, March 1986, April 1988, January 1989, February 1990, March 1991, February 1992, May 1998, April 1999 and June 2007.

However the study said: "The April 1988 flood event was the only event with enough data collected during the community consultation (DHI, 2010) for model calibration."

"It should be noted that the temporal patterns were taken from the Peats Ridge gauge which was the nearest available for this event

"The six-minute interval temporal pattern of Peats Ridge (Bureau of Meteorology gauge 61351) was scaled by the daily rainfall measured at Everglades Golf Course (BOM Gauge 61318) to produce this timeseries."

It said that 311mm of rain was recorded over 72 hours between April 27and 30, 1988.

"This corresponds to a six to seven per cent rainfall event.

"The sea boundary condition was taken from two of MHL's tidal gauge stations: Ettalong

212423 Station and Koolewong (Decommissioned in 2016) 212422 Station.

"The water levels along the coast between the two stations were linearly interpolated.

"There were no corresponding reported water depths for the April 1988 calibration event at the Kahibah Creek system.

"The Kahibah Creek Flood Study (Willing and Partners, 1991) considered two large flood events January 1989 and 7 February 1990 in the Kahibah Creek System as calibration events.

"The Kahibah Creek system has been modified largely after the study in 1991, including widening and lining of the channel paths, replacement of major structures and clearance of weeds.

"These changes are so significant that a calibration of the model against either of these events would not be relevant for the current study."





Skip Navigation Links.

Skip Navigation Links.

Peninsula
Planning
Portal
HERE
     Phone 4342 5333     Email us. Copyright © 2023 The Peninsula's Own News Service Inc ABN 76 179 701 372    PO Box 585 Woy Woy NSW 2256