This week saw a community information session, hosted by the RMS Communication & Stakeholder Engagement Team to present and discuss the findings of Stage One of the Batemans Bay Independent Coastal Impact Assessment and the proposed method and scope for Stage Two.
Harry Watson Smith of the Batemans Bay Boaters Association told the Beagle that he was given the The Independent Coastal Impact Assessment - Stage One document dated March 2019 submitted by GHD as an independent organisation to RMS as a study is prepared for presentation to the public.” Mr Watson Smith said “The stated aim of the report was to determine if the new Batemans Bay bridge, as compared to the old, would be “Worse”. Note the term “Worse” in a scientific modelling paper.”
“In the report not a single mention of the quantifiable parameters used to determine “worse”. The Executive Summary did not have a single categorical statement regarding the impact of the new bridge. The key finding stated “the impact resulting from the new bridge on hydrodynamics (big word for water movement) and sand transportation are predicted to be less severe than … the existing bridge”.
“Now lets return to the report’s quantifiable parameter of “worse”. We start to see that something is emerging, the words: water movement and sand movement but nothing else and definitely no three quantifiable parameters.”
“The GHD report then tries to justify the input data against the John Holland/Jacobs study. That is the construction company’s model that was used to convince RMS that their bid proposal was better than the competition to win the $274 million dollar contract.” The John Holland/Jacobs study was not peer reviewed by any outside academic for validity and maybe is now being validated or a due diligence exercise undertaken via the guise of a “Wave study” for the Surfside Group.
What input was used in the mathematical model? The same water volume estimates prepared by whom? The independent GHD company. “The sand supply in the water movement is an estimate from a previous now questionable model not actual data. Sea bed data taken from a not accessible data source but used by John Holland/Jacobs supplemented by lead line depths shown on a Hydrographic chart – more than likely done in 1920.” “Tide data used in the model evaluation taken from Bermagui 40 nm south of the Bay. Wind data from Moruya Airport. Yes located on the coastal plane not at the base of wide valley down which the west wind whistles. Sorry not good enough as excuses to use the same data as the construction company’s modelling and defiantly not independent,” said Mr Watson Smith.
“The March report then presented about 50 pages of colour diagrams attempting to show the results. “Now who reads that? Well the Association did and commented in a 5,000 word report “A Critical Analysis” which was to be reviewed and discussed in detail yesterday by RMS and three experts from GHD.
“Did the Association get any answers No. Nothing just a blank stare and, even the highly qualified GHD person, who either did the study or supervised it, when asked to explain Page 37 Section 6.1.2 figure 25 and 26 covering water velocity at a point opposite the north shore sat silent unable to answer the questions. “Why? Because it contradicts the very press statements being made to the public and shown at the three sheets of paper displayed at the pop-up event at the Community Centre.
Mr Watson Smith then described what he calls the Three Card (Criteria) trick.
“We find on these glossy sheets three parameters used to define “worse”
1. Water level
2. Current velocity
3. Bed level changes (sediment)
“Where did they come from? Not identified in the March Report and not anywhere on an available report. Just the glossy sheets with diagrams.
“The diagrams then attempt to show in red and blue if the new bridge has more impact than the old bridge compared to – wait for it... no bridge (based on the dubious input data discussed above.)
“They also exclude the flooding of the land area (CBD and Mackay Park but that can wait for another day) and the erosion on the north shore which is clearly indicated in the said Figure 25 and 26 of the March Report.
“The marketing material keeps referring to the new bridge having only three piers in the river and the piles are smaller as compared to the current six of the old bridge. Both three and six are in fact wrong – there are more piles, but here again don’t let facts get in the way of a marketing bluff. “Read the detail and you will find that there are in the current bridge two piles of an approximate diameter of 3.2 m while in the new bridge, being much heavier, requires three piles spaces further apart capped by a massive boat shaped construction. Sure their diameter is slightly less because you can’t drive a 3.2 m pile in to the river bed using the current pile driver - so you have to have three. “The bottom line of this bluff is that the impact on the water flowing past them will cause greater turbulence and therefore greater sand erosion not only on the river bed but along the north shore especially if they are not correctly aligned with the flood water flow.
“Did you get that? Aligned with the flood water flow. Now when questioned GHD refers the Association to RMS to answer that question about alignment which they do not. Why? Because the diagrams available to the public do not show them aligned to the water flow but square to the bridge path. So much more actual turbulence caused.
“Now did you see the three card trick? No, of course you did not. The community these days only reads the Executive Summary not the detail. They believe the glossy figures because a picture tells a thousand words. And if it is written then, as we all know from Google, it is believable.
“Where you happy with the slick words of the salesman selling their product -No.
“Did RMS consult with the community and can they now tick the box – the only YES.
Mr Watson Smith concluded “The Association awaits the final report, the brief, the reviewers report and the Stage two terms of reference and the proposal to spending of another $5 million.”
