Council moves on Pelican Waters Boulevard flood modelling

Sunshine Coast Council has today made available two reports to the public that explain the flood modelling in relation to Pelican Waters Boulevard.

The reports, Pelican Waters Drainage Review by Parsons Brinkerhoff and Pelican Waters Boulevard Hydraulic Analysis by SKM, relate to a recent report received by council that detailed a review of Pelican Waters Boulevard and hydraulic analysis of Duck Holes Creek.

Division 2 Councillor Tim Dwyer said he is pleased that the now released reports will provide a way forward to identify and implement a permanent solution to the flooding and drainage issues.

“We know that the detailed review and hydraulic analysis has confirmed there are flooding and drainage concerns for sections of Pelican Waters Boulevard between the roundabouts at Caloundra Road and Marmont Street,” Cr Dwyer said.

“I am happy that council has taken a collaborative approach with the Pelican Waters Estate and their consultants Cardno, to identify and implement a permanent solution to the flooding and drainage issues.

Cr Dwyer said it is important to reinforce the point that residents of Pelican Waters are safe.

“No residence in Pelican Waters has been inundated and commissioning of the reports was in no way connected to concerns about inundation in Pelican Waters Estate,” Cr Dwyer said.

“The design intent for Pelican Waters Estate was for flood waters from a 1 in 100 event to be contained to the lakes, streets and gardens, thus protecting property. The May 2009 event has been estimated to be more extreme than a 1 in100 event and during this event residents did not have water inundate habitable floor levels. This indicates that the design performed well under these extreme conditions.

“The flood immunity of the identified section of Pelican Waters Boulevard to a 1 in10 event has been identified as questionable, but does appear consistent with community observations in recent years.

“The solutions to be identified by Council are intended to return the 1 in 100 flood immunity to the identified sections of Pelican Waters Boulevard,” Cr Dwyer said.

A representative from Pelican Waters Estate Mr Phil Tyrer indicated that while they have been happy with the performance of Pelican Waters Estate during recent flood events the company is concerned for the residents of some of the older areas of Golden Beach to the east of Pelican Waters Boulevard.

“Pelican Waters Estate is happy to be collaborating with Council on solutions that will benefit these residents,” Mr Tyrer said.

The report to council specifically identified three areas requiring attention:

1. Flooding of Pelican Waters Boulevard at the northern end near Caloundra Road.
2. Flooding of Pelican Waters Boulevard at the section near Marmont Street.
3. A drainage issue north of Marmont Street, which presents as ponding in Duck Holes Creek and on the adjacent eastern side of Pelican Waters Boulevard, with the potential to cause public health and amenity issues.

A number of proposed solutions have been suggested including:

• Channel maintenance will provide improvements during the upcoming storm season. This work is underway and nearing completion.
• Improving the channel definition of Duck Holes Creek, opposite Russell Barker Park and south of Caloundra Road, to assist in the flow of water in Duck Holes Creek and away from Pelican Waters Boulevard.
• Longer term actions for flooding and drainage issues at the section of Pelican Waters Boulevard near Marmont Street are required and these will be addressed by further modelling and the collaborative approach between council, the Pelican Waters Estate and consultants.

As part of the release of these documents, technical stakeholders were given an opportunity to provide additional commentary relating to these two documents. Cardno, the consultants to Pelican Waters Estate and the designers of Pelican Waters Boulevard, have chosen to make their comments publicly available with the release of these documents. This additional clarity can assist the public in their interpretation of these reports.

Cardno have indicated that they welcome the opportunity for involvement in the review process and to improve the understanding of all stakeholders in relation to the design, modelling and operation of the drainage systems within and adjacent to the Pelican Waters development. This will ensure that the outcomes of the ongoing review of these systems satisfactorily address the issues of concern to all parties.

A workshop is planned with the technical stakeholders and it is expected that some modifications will be made to council’s hydraulic model that will improve understanding of flood risk in the area and assist in the design of the solutions that are intended to return the 1 in100 flood immunity for Pelican Waters Boulevard.

The channel maintenance works will be completed in the very near future and the hydraulic modelling to inform proposed solutions will be completed before the end of February 2012.

The reports and Cardno’s response are available on council’s website.

Pelican Waters Boulevard Hydraulic Analysis (Sinclair Knight Merz) [PDF 6.7MB]

Pelican Waters Drainage Review (Parsons Brinckerhoff) [PDF 5.3MB]

Cardno's Response to Pelican Waters Boulevard and Duck Holes Creek Drainage Review [PDF 144KB]