SEA Planning Responses to Estuarine Cumulative Effects of Watershed Urbanisation

Abstract

Strategic Environmental Assessment (SEA) and Cumulative Effects Assessment (CEA) are the focus of this research that investigated the evolving response in plans to the biologically undesirable accumulation of copper and zinc in a New Zealand estuary. Sources of metals are influenced by policies and plan provisions for land use, transport, stormwater management and boat moorings. During four decades of local government reform, plans responded to the scientific evidence of accumulation with increasingly sophisticated stormwater management. Despite the less explicit inclusion of SEA in New Zealand legislation, this research demonstrates for international audiences the concurrence of jurisdictional amalgamation; growing awareness and knowledge sharing across scientific, engineering and planning practitioners; and a steady improvement in plans to enable a marked slowing in cumulative effects (CEs) of urbanisation. A proposed Auckland Unitary Plan (PAUP) attempts to address some cumulative effects within watersheds now no longer divided by jurisdictional boundaries.

Advances in cumulative effects assessment and application in marine and coastal management

“…More advanced outputs were derived in some CEAs where estimates of the contribution of specific pressures or stressors to the state of VCs were derived (e.g. to estuaries, Van Roon et al, 2016;to coral reefs, Loiseau et al, 2021), enabling the identification of key leverage points or focal points for management measures (Loiseau et al, 2021). Only rarely were CEAs found to deliver estimates or measures of demographic change to VCs, which are valuable when estimating the significance of cumulative impacts, either ex post (e.g.…”

“…Finally, we highlight examples of research that offer insights into how to bridge the gap between CEA science and its application in policy and delivery. Common obstacles observed include fragmented legislation, poor alignment between ecological scales relevant to CEA and political scales relevant to management of cumulative effects, and the need for reliable, long-term datasets and the problem of shifting baselines (Davies et al, 2020;Hollarsmith et al, 2022;Van Roon et al, 2016). Enabling integrated coastal and marine planning and management involves long timescales, highlighting the need for long-term engagement and funding (Diggon et al, 2022;Van Roon et al, 2016).…”

“…Common obstacles observed include fragmented legislation, poor alignment between ecological scales relevant to CEA and political scales relevant to management of cumulative effects, and the need for reliable, long-term datasets and the problem of shifting baselines (Davies et al, 2020;Hollarsmith et al, 2022;Van Roon et al, 2016). Enabling integrated coastal and marine planning and management involves long timescales, highlighting the need for long-term engagement and funding (Diggon et al, 2022;Van Roon et al, 2016). The need to include diverse values, including those of indigenous peoples, into decision making is discussed by Davies et al (2020) and Diggon et al (2022).…”

“… Which statistical frameworks can be used to ensure that uncertainty arising from data limitations is captured and expressed coherently in CEA outputs? Understanding the delivery landscape: Noting the observation that CEA should remain independent of decision-making (Stelzenmüller et al, 2020), there is a clear need for CEA research to have greater interaction with decision makers, to align with policy and delivery information needs (Jones, 2016;Van Roon et al, 2016). Therefore, key research questions are:  Relative to CEA, how coherent are existing governance systems?…”