News

Levee banks need a 20cm lift

Levee banks on both sides of the Clarence in Grafton would need to be raised when the new bridge is built.
Levee banks on both sides of the Clarence in Grafton would need to be raised when the new bridge is built. Debrah Novak

SOME levee banks on the north and south sides of the Clarence River may be raised 20cm when the second Grafton Bridge is built.

The Environmental Impact Statement released by Roads and Maritime Services earlier this month shows the construction of the new bridge will cause upstream river heights in a one-in- 20-year flood to increase by 10cm.

The study also looked at the effect of the increased flood heights on 58 rural properties outside the levees.

It said these increases are typically less than 0.1m in a 100-year ARI event.

The report recommended further investigations to quantify this risk and identify additional mitigation measures (if possible) to be completed during detailed design.

This would include a habitable flood level survey and comparison to existing and predicted flood levels, followed by consideration of additional mitigation options for these properties.

The proposed mitigation measures also include a detention basin and pumping arrangement to provide a flood-free approach road to Grafton during a 20-year ARI event.

Climate change will make the communities of Grafton and South Grafton vulnerable to impacts but the proposed scheme does not significantly alter this increase in future risk.

Instead it recommends future stages of this project match future "climate adaptation" strategies adopted by Clarence Valley Council.

The report notes existing flood evacuation arrangements within Grafton will generally benefit from the proposed project, which will improve access to higher ground in South Grafton, subject to constraints of traffic congestion within the business district of Grafton.

Raising the levees

 Mitigation Option 2: Raising 3.7km of levee on the north bank and 7km of levee on the south bank of the Clarence River by 0.2m.

 Mitigation Option 4: Raising 3.7km of levee on the north bank, 4.7km of levee on the south bank and raising a 550m length of the Gwydir Hwy to an elevation of 7m AHD (current elevations are between 5-6.5m AHD).

Topics:  clarence river, eis, grafton bridge, rms




Where will 2016 sit in July Carnival history?

Hong Kong based owner Patrick Fu and his son bring back Ramornie Handicap winner Smart Volatility back to scale.

We look back at the big moments of the 2016 July Racing Carnival

NSW economy not so good according to business survey

A recent survey reveals businesses in the Northern Rivers are less optimistic on the current state of the NSW economy than earlier this year.

Survey shows Northern Rivers businesses less confident.

Latest deals and offers

Superheroes of the big screen enjoy sounds of Splendour

CHRIS Hemsworth and his Avengers mates drop by Byron festival.

Indigenous artist shows tourists secrets of Aboriginal painting

Ever thought "I could do that" about Aboriginal art?

Dynamic pics from Splendour Day 1

The Strokes perform at Splendour in the Grass 2016. Photo Marc Stapelberg / The Northern Star

Check out the latest pictures from Splendour in the Grass.

Bindi Irwin: 18 magic photos to mark her 18th birthday

Bindi Irwin with a python.

Photos: Bindi Irwin from babyhood to 18

Aussie director makes his mark on new Roots mini-series

Malachi Kirby as Kunta Kinte in a scene from the TV series Roots.

BRUCE Beresford behind final episode of remake of iconic series.

Wham bam, thank you TAM

Regional TAM is increasing its audience measurement services by 50%.

Regional television viewers finally getting the credit we deserve

You can own this Queensland town for just $1

Yelarbon

Unprecedented auction of town's business centre with no reserve

Work starts on $15M Caloundra apartment building

Turning the first sod at the Aqua View Apartments site in Kings Beach are (from left) husband-and-wife developers Alex Yuan and Stella Sun with construction company Tomkins director Mike Tomkins and Councillor Tim Dwyer.

Developers excited about addition to Kings Beach skyline

Plans revealed for 1500-lot 'master-planned community'

Precinct will be bounded by Boundary St and Shoesmith Rd

Ecco Ripley sales run sparks prime release

MOVING IN: Sekisui House has announced the release of more residential blocks at Ecco Ripley.

Sekisui House is preparing to unveil more land at Ecco Ripley

Massive residential 9-storey high-rise hit by delays

An artist’s impression of the eight-storey-high apartment complex that Bernoth Holdings wants to build in South Toowoomba, next to the City Golf Club.

Developer struggles to get approved high-rise development started