Derby Tidal Power Proposal

Derby Tidal Power – Green Energy?

On face value, the proposal for tidal power might look like being an environmentally friendly project; however there are some serious environmental concerns (see below).

The project has yet to be assessed by the Federal Government under the Environmental Protection and Biodiversity Conservation Act.

It is proposed that the electricity generated would power mines in the Kimberley, mines which currently do not exist.

Environmental concerns:

1.  1,500 hectares of mangrove communities destroyed

The proponent says that 2,300ha of mangroves would be regrown but the EPA has challenged this and stated:

“Due to the larger loss of mangroves associated with the proposed variations and the continued uncertainty associated with the proponent’s predictions on mangrove regeneration responses, it is appropriate for the EPA to reiterate its conclusion from Bulletin 942 that the EPA’s objective for mangroves cannot be met.”

(Environmental Protection Authority, Bulletin 1071, October 2002  p8-9)

2.  Damage to a proposed nature reserve

The Department of Conservation and Land Management has expressed serious concerns about the potential negative on the proposed nature reserve:

“CALM expressed concern over the potential impact on the proposed nature reserve from changes in surface and groundwater flow patterns”

(Western Australia EPA Bulletin 942, 1999; 28).

 3.  Dust storms in Derby

The Environmental Protection Authority:

“Dust levels in Derby during certain times of the year, when north east winds are blowing, are already at a nuisance level. Concern has been raised that causing large areas of mudflats to become permanently dry as they would no longer be subject to tidal inundation during spring tides, would further increase the dust levels during north east winds.

The proponent has stated that the 3 km separation distance between Derby and the eastern arm of Doctors Creek would reduce the likelihood of a dust problem in Derby and that the crust of salt that would be left on the mudflats would act to seal the ground and prevent dust generation. However, the long term effectiveness of this method has been questioned.”

(EPA Bulletin 942, p38)

4.  Threatened species

A number of threatened species would be at risk:

 a.   Freshwater Sawfish (Pristis microdon) – Vulnerable (EPBC Act)

“It may be worth noting that Pristis microdon is listed as critically endangered by the IUCN. Although Pristis microdon is widely regarded to be restricted to freshwater and/or the lower salinity in estuaries, it is occasionally caught by gill net fishermen operating in the Arafura Sea and has been found in the Robinson River just to the north of Doctor’s Creek. Furthermore, whilst Pristis microdon is extremely common throughout the Fitzroy River, none of the fish caught were mature. In contrast, the local professional fisherman often catches large mature animals in and around Doctor’s Creek“

(Morgan, Gill, White and Thorburn, 2002)

b.  Northern River Shark (Glyphis garricki) – Endangered (EPBC Act)

“The results of this study suggest that the tidal creeks of King Sound, including Doctors Creek, may be an important habitat for the critically endangered Glyphis, with these specimens representing almost half of all those known.”

(Thorburn et al. 2003)

“The feeder creeks of King Sound, and in particular those of the macrotidal Doctors Creek and Fitzroy River mouth, may be an important refuge for Glyphis sp. C.”

(Thorburn and Morgan 2004, pp5 -7)

5.  Snubfin Dolphin

The snubfin dolphin is found only in Northern Australia. They have been seen in Doctors Creek but no studies have been done by the proponent.

6.  Lack of information

EPA again:

“A range of uncertainties exist in relation to the influence of the proposed project on the biological systems within the tidal flats, the two branches of Doctors Creek, the mangroves are and the area of King Sound adjacent to the barrages.

 The EPA would require further information on these current ecosystems and the potential effects of mangrove modifications and sedimentation on a range of key biological indicators and their productivity. These indicators would include the crabs (which are currently utilised by local people for food), the mangroves (which are dominant species), micro-organisms in the tidal flats and estuarine systems (which may reflect changes in tides and sedimentation). The proponent should also seek more advice from scientists who have studied similar ecosystems around the world for this selection of potential bioindicators.”

(EPA Bulletin 942, Appendix 3)

Here are some expert scientific reports on concerns about the proposal:

  1. A critical appraisal of the consultative environmental review: Derby Tidal Power Project Doctors Creek, Kimberley. Joint report by: V & C Semeniuk Research Group Derby Tidal Power Project – Semeniuk, Critical Appraisal
  2. The DERBY TIDAL POWER PROJECT: An Examination of the 1997 Consultative Environmental Review for Environmental Effects that might necessitate abandonment of the Project Dr. Graham R. Daborn, Acadia Centre for Estuarine Research, Acadia University Nova Scotia Canada Derby Tidal Power Project -Daborn, An Examination
  3. Comment on the “Guidelines for the Content of a Draft Environmental Impact Statement on the Derby Tidal Power Project, Western Australia” (Reference No. 2010/5544). Graham R. Daborn Ph.D.,  Acadia Centre for Estuarine Research, Acadia University Daborn Comment on 2010 Derby Project Draft EIS Guidelines