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Auckland’s erosion and sediment control program – telling the story
Developers must look at integrated impacts that do not stop at the boundary lines of their properties.
George Carl
When Auckland’s erosion and sediment control training program first started, Brian Handyside (my co-trainer) and I thought there might be two or three years of training to deliver, then everyone would be trained and we could stop. What actually happened turned out to be quite different: 15 years later, the program is still going and has been endorsed by major government agencies that require their service providers to attend. Moreover this highly successful program has – like the programs we looked at when starting out – inspired a number of similar programs. We’ve even had people from other countries attend our workshops to find out what we do.
So successful was the program that we ended up creating a whole new profession: environmental managers on large construction sites. These highly skilled people move freely between development, engineering design and contracting companies, as well as environmental regulatory agencies and specialist consulting firms. Over the years I’ve seen how this exchange of knowledge and perspective adds tremendous value to each of these organizations.
How did it all begin?
Figure 2 Auckland and New Zealand
The Auckland Regional Council (ARC) was one of the 14 regional agencies with environmental responsibilities in New Zealand, shown in Figure 2. In 2010, the ARC and the region’s seven local councils were amalgamated into a new Auckland Council that now combines all the previous councils and their functions.
Straddling three of the northern North Island’s biggest estuaries and any number of smaller ones, Auckland is home to the country’s biggest urban area and more than 1.5 million people (over a third of the country’s population).
The region will continue to grow to around two million people by 203623 – only 25 years from the date of writing. By 2050, 75% of all the world’s people will live in cities – and 2.6 million of them will live in Auckland24. All this new development will take place in an already heavily developed area that occupies a mere 2% of New Zealand’s land area.
It’s a ‘perfect storm’ of growth-related risks and environmental vulnerability for the beautiful harbors that the 1999-2000 America’s Cup yacht races showcased to the world.
Rapid population growth in the late 1970s highlighted the environmental risks posed by development, including:
To the consternation of the public and agencies alike, these risks contributed to big, unsightly plumes of sediment in streams and harbors, clogged streams and stormwater systems, localized flooding and deposition of sticky yellow clay on popular beaches.
A number of erosion and sediment control guidelines had been produced in the USA in the early 1970s, and a national New Zealand equivalent was published in 197525. The Auckland Regional Water Board, a department of the ARC’s predecessor, the Auckland Regional Authority, then produced a guideline specifically for the Auckland Region in early 197926.
Widespread concern about sedimentation and other development-related issues led to the setting up of the three-year Upper Waitemata Harbour Catchment [watershed] Study, also in 1979. The Study was a collaborative research project between the University of Auckland and the Water Board. Concerned about the area’s vulnerability to uncoordinated development, the research team hoped that understanding of environmental processes would inform land and water management practices to reduce environmental harm.
By 1983, the Study had produced many guidelines, reviews and technical reports to guide the conservation and wise use of land and water resources during development of that catchment and other similarly vulnerable catchments in the country. Scientific reviews were prepared on stream and harbor ecology, ecosystem energy patterns, freshwater and land resources, land and water use, stormwater control, harbor sediments, tidal flushing and legal aspects of land and water management.
To help with land and water use planning and development, the study also produced eight practical guidelines on:
Despite having only 13 pages of technical content, the 1983 Earthworks erosion management guideline27 was remarkably prescient, highlighting as it did the need for good land use planning and urban design, comprehensive catchment planning, low-impact development and minimum
