Lessons from the past

With the prospect of Westport, what lessons do the past 70 years of human impacts on Cockburn Sound offer us?

By James Mumme, Brand Greens

My knowledge of science comes from reading, talking with scientists and doing science locally. My experience with the Sound dates from 2001 when I joined the Rockingham Bays Seagrass Monitoring Group, a citizen science volunteer group supported by the then Department of Conservation and Land Management (CALM). For six years we recorded seagrass health and growth from Mangles Bay to Beach Point in the south of Warnbro Sound. From 2006 to 2018 I worked against the Mangles Bay Marina project. From 2013 I served for six years as community member of Cockburn Sound Management Council (CSMC).

I'm not absolutely opposed to a minimal version Westport provided the first three principles in the Environmental Protection Act 1986 are properly applied ‒ the precautionary principle, and the principles of intergenerational equity and of conservation of biological diversity and ecological integrity. In this article I've tried to distil what I think is important for development planning and environmental assessment in relation to Cockburn Sound. Westport's Beacons 7, 10, 11, 12 and 13 do contain many worthy plans and commitments to protect Cockburn Sound and the study commissioned by CSMC on Drivers, Pressures, State, Impacts, Responses Assessment 2017 is valuable. This article presents eight hurdles Westport needs to overcome. I have described problems affecting Cockburn Sound, how they were dealt with, what the consequences have been and what can we learn for the future.

PROBLEM 1: WHERE TO PUT INDUSTRY

After WW2 the State began growing apace and needed somewhere to put an oil refinery and various smelters that was not far from Perth, had nearby space for workers and offered a protected port for things that are smelly and explosive. The solution was to locate these industries along the Kwinana Strip and construct ports to service them. Consequences included polluting the waters of the Sound and the eventual construction of ten jetties or ports, as well as a lot of air pollution ‒ there are at least 14 smokestacks visible in the header photo.

There are many other current impacts. The Sound has seven jetties on the east side ‒ ALCOA, BHP, BP, CBH, Kwinana Bulk Jetty and one other jetty, the Northern Harbour in Jervois Bay and more on the west side. All required dredging during construction and may require ongoing dredging. To the north there is a dredged channel from Fremantle into Cockburn Sound and as well Cockburn Cement has licence to extract nearly 3 million tonnes of shell a year with a dredging impact of nearly 800 ha (including 168 ha of seagrass)(Environmental Protection Authority Perth, Western Australia Bulletin 1033 November 2001).

In the middle of Cockburn Sound there is also the Desalination Plant outlet which has been found to raise salinity levels in its vicinity but so far nothing else. Polluted groundwater plumes are known to be progressing westwards into Cockburn Sound (DWER Contaminated Sites Act 2003 Basic summary of Records Search Response. Report generated 09/04/2019).  The Northern Harbour constantly fails to meet standards and the BHP Nickel Refinery site has been declared a contaminated site with unsafe levels of four chemicals being found leaking into Cockburn Sound (Cockburn Sound Management Council, The State of the Sound Report 2018). The water there was found to exceed non-potable guidelines and EQCs (Effluent Quality Criteria) for recreation and aesthetics in 1990 (Monk, R. & Murray, F. 1990. Heavy Metal Contamination in the Marine Sediments of the Cockburn Sound Region. Murdoch University)

On the west side of the Sound there are at least three naval jetties and currently a three-year major expansion is underway with thousands of tonnes of rock being dumped. No environmental approvals were required or have been sought for this work though Defence has been conducting research into pollution of groundwater, soil and sea water by the Per- and Poly-Fluoroalkyl Substances (PFAS) used for firefighting. They have found elevated levels in soil, pore, ground and surface water and recommended Ecological Risk Assessment research be undertaken in 2018 (PFAS Stirling Report PFAS Report May 2018 : Executive summary). Elevated levels of the anti-fouling agent Tributyltin (now banned) have been found in sediments in two places and at times in waters around jetties (Investigation into Tributyltin (TBT) Contamination in Cockburn Sound. Oceanica Consulting Pty Ltd 2006).

LEARNING 1: HOW MUCH GROWTH IS ENOUGH ?

The learning from this is one the whole world is confronted by ‒ you can't just go on expanding and using up nature endlessly without consequences. In the long term we need a circular economy in which there is no such place as 'away' and each part of our environment is harmoniously in some way connected with each other part.

Before the decision is made to go ahead with Westport, the following need to be assessed and their cumulative impacts re-assessed. First the potential impacts of Westport on water quality and seagrass need to be assessed: impacts from dredging, ship movements, reclamation and loading. A second assessment is needed into the combined impacts of the ten ports or jetties already operating. Third is an assessment of chemical pollution of groundwater and its leaching into Cockburn Sound. Fourth the cumulative impacts of all of the above impacts of Westport need to be assessed and the Precautionary Principle honestly invoked.

PROBLEM 2: ACCESSING GARDEN ISLAND

Until the 1970s the only access to Garden Island was by boat. With the decision in 1960s to expand Stirling Navy Base the lack of road access to the island became a severe problem.  The solution was to construct a causeway with two bridges in 1973. Ignored were the consequences of restricting the flushing of water through Cockburn Sound: murky water staying longer in the Sound reduced sunlight reaching seagrass blades thereby shutting down photosynthesis. This has exacerbated the nutrient and pollution load in the water.  The result of these in combination with other issues has been the loss of 80% of seagrass nurseries leading ultimately to bans on taking snapper, crabs and herring and to mass fish deaths. 

As well as Westport there is an existing proposal to construct a rock groyne along the beach in the south for the Port Rockingham Marina though lack of funding has been holding this up since 2014. Nevertheless it is still an approved development. It could go ahead and so its potential impacts should be included.

LEARNING 2: EVERYTHING IS CONNECTED TO EVERYTHING ELSE

We need to take into account impacts on the ecological needs of a partly enclosed water body for good flushing and clean water. 

Before Westport goes ahead, the lack of good flushing within the Sound needs to be remedied. Modelling studies quoted by Westport (Beacons 7 and 12) argue that removing the Causeway would make little difference.

I don't see how this could be so given that, before the Causeway went in, the seagrass was in good health and covered five times what it covers now.

PROBLEM 3:  IGNORANCE

Until the 1990s we had no idea about the extent of the loss of seagrass, not to mention its consequences. The solution for the past thirty years has been to clean up the water. Water quality has significantly improved due to capturing of storm water and limiting of releases by industry. However, the disappointing consequence is that while the extent of seagrass coverage has increased, the density of shoots has reduced meaning that there is roughly the same amount of seagrass to provide habitat and food.  Attempts are being made to find out why ‒ one hypothesis is the presence of acid sulphate soils in the sediments though they have been under the seagrass for thousands of years. Information about pollution plumes is only now coming to hand. One problem is lack of timely publication: CSMC's State of the Sound Reports typically take over two years to be published after the research is done. I understand the next one is presently with the Minister.

LEARNING 3: CURRENT COMPLETE INFORMATION IS NEEDED

We need to have current information about as much of the state of the Sound's ecology as possible to solve the seagrass riddle.

Therefore before planning proceeds further, better information about the state of the Sound is needed (Beacon 11 says FY20/21 will see this). This needs to include real time water quality and temperature, plus seagrass extent and health, epiphyte communities and their health, invertebrate numbers and health, and vertebrate species presence. The baseline study results produced by Cockburn Sound Management Council need to be followed up and extended to promptly provide as near to real time information as possible. This could mean that any deterioration can be picked up promptly and dealt with by appropriate action including suspension of dredging. When the Preliminary Environment Review (PER) comes out, we need to call for this.

PROBLEM 4: DEMAND FOR LAUNCHING RAMPS

Shortage of launching ramps for increasing numbers of powerboat owners has been an ongoing problem. The solution was for Rockingham Council (part funded by Department of Transport) to construct launching ramps on the west side of the Causeway. It's a great facility. However in consequence, sand being transported from the west was blocked by the Causeway and filled up the lagoon of the launching ramps making them unusable except at high tide. The next solution was in the short term to dredge the lagoon. One year a storm filled it up again a week after it was dredged! So a sand trap was created outside the lagoon by constructing two groynes. The outcome has been that the sand trap fills up and still needs dredging twice a year. A separate consequence may have been the erosion of a six metre tall sand dune at the camp school further along the beach.

One last attempt to solve both problems has been to further slow sand movement by constructing an artificial reef from the beach further west. But again this year the sand had to be dredged from out of the lagoon itself and from off the concrete boat ramps (City of Rockingham Agenda Planning and Environment Committee 19 October 2020). In September 8,200 cubic metres was dredged out. The cost of this to Council was estimated to be $120,000 in FY 2019-20.

 

LEARNING 4: DON'T MAKE ASSUMPTIONS ABOUT SAND

The learning for Westport's risk assessment is to not ignore the size, impact and cost of sand transport along this coast and to not rely on existing models. The increasing strength of storms and the gradual rise in sea levels and storm surge levels needs to be taken into account. Even though Westport is proposed for the eastern side of the Sound, what will be the potential impacts of storms on the port and on the dredged channels?

PROBLEM 5: THE SOLUTION BECOMES THE PROBLEM

The next problem is what to do with the sand pile because there are limits to how much can be stored. In October 2020 the pile of sand was six metres high and 50 x 30 metres wide.

The solution used so far has been to truck the sand for beach replenishment elsewhere in the City. It's been trucked 3 km to Mersey Point where it was made into a slurry with seawater and piped 700 metres to Penguin Island to rebuild a beach where erosion was threatening buildings. It's also been trucked 500 metres across the Cape to Shoalwater Bay. The beach there has been eroding at up to 4 metres a year due to sea level rise and intense southerly storms. One unfortunate consequence is that the replenishing sand has often been eroded within months. Because sand drift on the coast is from south to north, the same sand ends up going into the Lagoon again! The latest proposal is to construct an underground pipeline to pump the sand across the Cape to the beach. An expensive merry-go-round in the sea!

LEARNING 5: BEWARE SIMPLE ENGINEERING SOLUTIONS

Before Westport is commenced, analysis of risks from sand movement and the costs of dealing with the worst case scenarios should be undertaken.

PROBLEM 6: POLITICAL OVER-ZEALOUSNESS

The energy that the ALP is putting into Westport is not dissimilar to what the Barnett Government put into the Mangles Bay Marina (MBM) boasting billions in business benefits, thousands of tourists and hundreds of jobs. This 12 ha inland marina and canals lined with houses would have involved dredging a channel through Mangles Bay and risk of poor flushing of the marina due to having only one entrance. The proposal was pushed hard by the Barnett Government with help from the Howard Government and with ambiguous support from the Labor leadership. It passed all State and Commonwealth environmental assessments albeit with conditions.

So confident of success was the Barnett Government that just before the last election it forced leasees along the waterfront to remove all their buildings. Twelve months after the 2017 change of Government, the Minister for Planning reluctantly rejected rezoning the area as a result of which the whole proposal was sunk. In consequence more than 1 ha of low cost housing had been removed and the area became infested with weeds and rubbish. Local people loved driving down to the beachfront to eat lunch and watch the sunset. Anti-social behaviour and camping were reported so warning signs, a fence and then bollards and limestone rocks were installed to solve the problem, at cost to taxpayers.

LEARNING 6: BEWARE OF OVER-CONFIDENCE

Claims by politicians of future economic benefits and jobs need to be examined critically. One approach might be to compare historical claims of benefits and jobs of projects that either were completed or failed to be built with Westport. Proposers have been good at weighing up apparent costs and financial risks in their favour but less good at acknowledging physical environmental risks let alone ecological ones.

PROBLEM 7: BEWARE OF OFFSETS

To deal with the losses of seagrass due to dredging the access channel to the MBM, the proponent would have been required to replant 2 for 1 ha of seagrass and to continue until success was achieved. However, the evidence of success of transplantation was equivocal at best (Global analysis of seagrass restoration (Journal of Applied Ecology 2015 doi: 10.1111/1365-2664.12562 and see photos in Transplanting Posidonia Seagrass ... A Practical How to Guide 2013). Also, the requirement for success considered only shoot numbers, not a requirement to match the lost ecological communities of epiphytes so crucial to vertebrates’ breeding success.

LEARNING 7.  ENSURE ANY OFFSETS ARE REALLY LIKE FOR LIKE

Offsets are mentioned twice (Beacon 7) but in both places in context of social harm mitigation, not environmental mitigation. From the mapping used in Beacon 12 I believe that some seagrass will be lost from dredging, though the project for the current 12 months is to map seagrass. If Westport proposes an offset for seagrass (or anything else like Banskia or Acacia scrub that may be lost), they should be required to demonstrate not only like for like in terms of a few major species, but also sufficient elements of the whole ecological community that will be lost to justify the offset.

A review of environmental assessment in WA must include a thorough analysis of the use and misuse of offsets and more stringent requirements before offsets can be approved.

PROBLEM 8: CONSULTANTS' RESEARCH

These problems involve both ethics and money. Experiences with both Roe 8 and MBM lead to conclusions that consultants hired by proponents may either gild the lily and gloss over the gaps or else find their reports reworded in the Public Environmental Review with the result that risks get minimised and benefits maximised. With the MBM I personally know three scientists who gave objective and independent advice and none of them was paid for by the proponent and their work did not appear in the Public Environmental Review.

I know from experience that interference by Ministers or their offices may lead to removal of appeals against a government project from the very government agencies tasked to protect them. 

Lack of funds by community-led opponents of projects may lead to research projects not being undertaken. Preserve Point Peron failed to find $5,000 for a relatively simple groundwater study.

LEARNING 8: SUGGESTIONS NEEDED

There is little we can do until there is adequate funding for the Environmental Defender's Office and/or some kind of environment court or tribunal that can ensure objective and independent evaluation of research, and thorough application of the precautionary and intergenerational principles (See new GWA Environmental Protection Policy).

Header photo: How can we ever learn? A litany of errors ‒ Kwinana Industrial Area and site of Proposed Westport, part of the Causeway, the launching ramp lagoon, sand trap, groynes and the pile of sand.

_{[Opinions expressed are those of the author and not official policy of Greens WA]}