Water Journal : Water Journal April 2013
WATER APRIL 2013 98 Feature Article • Ef ciency -- to report on the extent to which the program delivered against its agreed activities and expenditure and explanation of any variations; • Effectiveness -- to determine whether the program achieved its desired outcomes and any reasons for program over- or under-delivery. While a signi cant amount of the evaluation effort has been associated with enabling an evaluation of the Stage 2 of the Tuggerah Lakes program at its completion in June 2013, many of the discussions with the partners have highlighted examples of how some of the sub-programs have been adaptively managed during implementation. For example, the streambank rehabilitation program incorporated expert opinion, design and observation at sites to adapt rehabilitation approaches at some streambank sites. Ensuring that appropriate evaluation processes are in place to enable ongoing review of an intervention against the intent of a program is critical. This recognises that evaluation is not just about making judgments and reporting them at the end of the program, but is also critical during program implementation so that a program can be continually strengthened on the basis of new evidence to support change. A case study of the saltmarsh rehabilitation sub-program is presented next, to provide an example of the adaptive processes that have been implemented under Stage 2 of the Tuggerah Lakes rehabilitation program. CASE STUDY: SALTMARSH REHABILITATION PROJECT BACKGROUND TO THE SALTMARSH SUB-PROGRAM Saltmarshes are a unique component of coastal estuaries in Australia that exist at the land and water interface. Conditions in these areas are highly dynamic and biota must be adapted and specialised to cope with varying degrees of salinity, tidal inundation, competition and disturbance. The unique position of saltmarshes allows them to function in several ways including ood and erosion control, storm surge buffering, water quality improvement and seagrass wrack assimilation. The need to rehabilitate saltmarsh habitat within the Tuggerah Lakes Estuary was highlighted in the Estuary Process Study as a high priority management issue. This recommendation was then carried through as a priority program under the Tuggerah Lakes EMP. Receipt of funding from the Caring for our Country initiative then enabled implementation of the passive and active saltmarsh rehabilitation programs beginning in 2009 and continuing for the duration of Stage 2 of the program. PASSIVE SALTMARSH REHABILITATION Passive saltmarsh rehabilitation includes controlling localised threats to saltmarsh and supporting natural regeneration with the aim of increasing the long-term viability and extent of existing saltmarsh. Identi ed threats to saltmarsh around the Tuggerah Lakes Estuary include mowing, trampling, compaction, vandalism, weeds and altered hydrology. The passive rehabilitation program includes highly accurate mapping and demarcation of saltmarsh in susceptible areas, application of mowing restrictions, fencing and signage in some places, signi cant community and council staff education and control of semi salt-tolerant weeds. Council has worked closely with NSW National Parks and Wildlife Service (NPWS) Of cers, the Hunter-Central Rivers Catchment Management Authority, the Community Environment Network, Darkinjung Local Aboriginal Land Council and the local community to deliver these projects. Development of good working relationships with these authorities and agencies has been crucial in the delivery of these programs. Further to this, another real key to the success of this program was the excellent education, liaison and consultation with the community and land owners to build rapport. This led to some important and unexpected outcomes with many adjacent residents becoming real ambassadors for the saltmarsh program. ACTIVE SALTMARSH REHABILITATION Reconstruction of saltmarshes in non-tidal estuaries is a largely untested activity in Australia. Around the Tuggerah Lakes estuary, Council has previously attempted small-scale saltmarsh rehabilitation projects at the mouth of Tumbi Creek and at Rocky Point using natural regeneration as the primary mechanism for recolonisation. The active saltmarsh rehabilitation program aims to recreate an appropriate saltmarsh habitat by re-grading elevated foreshore areas to reinstate hydrological links with groundwater, overland ow and, most importantly, inundation from the estuary. Once an appropriate grade is established, local provenance native saltmarsh plants are replanted and then carefully maintained for up to ve years to support complete establishment of a fully functioning plant community. The active saltmarsh rehabilitation sub-program also utilised innovative techniques not before used in the estuary and faced a number of challenges from its inception. Three examples of this that required adaption included: 1. The need to protect new saltmarsh plants from excessive wind-driven wave erosion and deposition of wrack resulted in the use of a combination of ecologs and a purpose-built wrack fence; this was further adapted at later sites by retaining a fringe of original vegetation along the foreshore. 2. Wrack had been used in small amounts as a soil conditioner but resulted in the Figure 3. An area of Tuggerah Bay before saltmarsh works were undertaken.
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