A reduction in nutrients and sediment which would impact seagrass communities, dugongs, fish habitas, fish creches, possibly crustacea spawning rythms, massive explosion in mangrove fecundity due to hypersaline effects (less fresh) , potential reduction in wader bird food resources, potential collapse of mullet, flathead, barramindi, banana prawn stocks, and other estuary dependent species. ALL species, habitats and marine ecotones are linked , right up to the whales, what effects occur along the chain must be investigated, not blindly ignored and all of the economic sectors which rely on this linkage must start whinging very, very loud to the people of brisy.

FOSS Posted: Wed Aug 02, 2006 2:51 pm    Post subject: ramsar effects

The WRP identifies 3 "nodes" on the Mary River downstream of the dam wall, where certain flow objectives are identified. As previously noted, some of these flow objectives have "no teeth" because the legislation uses weasel words such as "minimise the extent to which ...".

There are some other troubling aspects related to the monitoring nodes which I believe are worthy of comment.

The nodes are:

• Node 1: River Mouth, approx 205km downstream of dam wall
  
• Node 2: Home Park, approx 114km downstream of dam wall
  
• Node 3: Fisherman's Pocket, approx 34km downstream of dam wall
  

In the legislation, one of the key "Medium to High" flow objectives (see pages 61-63) is the mean annual flow, expressed as a percentage of the mean annual flow for the pre-development flow pattern, or %MAF. In the Save The Mary River Technical Note Series (1) it is demonstrated that %MAF is a poor statistic for describing river flow behaviour. Nonetheless, it is probably the simplest to understand, and also the most often quoted by the Premier and other politicians.

The %MAF flow objectives in the legislation are:

• Node 1: must be at least 85%
  
• Node 2: minimise extent to which it is less than 79%
  
• Node 3: minimise extent to which it is less than 70%
  

My concerns are:

1. Why is there no monitoring node at the dam wall? Historical data at the Dagun Pocket monitoring station (approx 1km from wall) is publicly available dating back to 1957, and I understand the DNRM has 110 years of historical data. The flow models used in the WRP must certainly model the flow at this point, or it would be impossible to model downstream flows.
   The flow disruption on the Mary River immediately downstream of the dam wall, before the inflows from other creeks, must certainly be greater than at the three nodes specified in the WRP. Could this be why there is no monitoring node at the wall location?
   
   
2. By correlating the publicly available historical flow data from Dagun Pocket, Fisherman's Pocket and Home Park, it is possible to back-calculate the likely %MAF at Dagun Pocket based on corresponding figures from the other nodes.
   79% at Node 2 (Home Park) corresponds to around 51% at Dagun Pocket.
   70% at Node 3 (Fisherman's Pocket) corresponds to around 59% at Dagun Pocket.
   
   
3. Node 1, at the River Mouth, is not actually a real monitoring station. It is a "virtual node". There is no actual historical measured data at this point. This is a very serious concern, especially given that it is the only node in the legislation that doesn't have weasel words in the %MAF flow objective. I make a living from modelling flow rates in industrial process plants, and I can assert that any flow model is only as good as the data against which it is calibrated. We call this principle "garbage in, garbage out".
   At the other nodes, the flow models are not only calibrated against up to 110 years of measured data, but it will also be possible to continually benchmark the modelled flows against real measurements. Not so for Node 1 at the River Mouth. The WRP legislation does not include a single word as to how the flow at Node 1 will be modelled, calibrated or monitored.

Darren E Posted: Fri Aug 11, 2006 2:16 pm