Posts Tagged ‘salt marsh’

Consultation about designating the Devon Avon Estuary as a new Marine Conservation Zone

DEFRA is consulting until 20th July 2018 about designating new Marine Conservation Zones, seeking any fresh information that might influence the decision.  The summary sheet for the Avon Estuary proposal is available here – Devon Avon Estuary Factsheet

At present, the proposal does not include South Efford Marsh or the full extension of the Bass Nursery Zone out to Burgh Island.

The ACA, unsurprisingly, fully supports such a designation and our suggested modifications as a means of protecting the marine life of the estuary from unwarranted change, development or exploitation.

Our formal response is available for inspection here :- MCZ – Devon Avon Estuary

DEFRA reply – All responses will be considered before Ministers make their final decisions on which sites will be designated in the third tranche. We aim to designated this tranche within 12 months. Final decisions on which sites will be designated will take into account any relevant information submitted as part of this consultation. We will publish details of evidence received and a full Government response to these together with the final decisions on each site within 12 months. This will be placed on the consultations section of the Government web site.

An additional rationale for designating the estuary as an MCZ was sent to Natural England in early November 2018, as follows:-
Further to my original submission about designating the Avon Estuary in South Devon as a Marine Conservation Zone or MCZ  (response I.D. = ANON- PGP8-UYCU-5), I hope it is not too late in the decision-making process to draw your attention to a feature of the estuary which I overlooked and which also was not mentioned explicitly in DEFRA’s Factsheet, although others may have mentioned it in their submissions.
This feature concerns the role of the inter-tidal salt marshes and mudflats of the estuary as important stores of ‘blue carbon’.  As I’m sure your scientists at NE will readily acknowledge, these habitats are under constant threat from sea level rise, on the one hand, and development ’squeeze’, on the other.   It becomes particularly important to conserve such carbon ’sinks’ in the face of climate change, irrespective of what individual species may dwell there. The following, italicised, passage succinctly presents  the argument for conservation; it is taken from  the website of
‘Blue carbon’ is the carbon stored and sequestered in coastal ecosystems such as mangrove forests, seagrass meadows or inter-tidal salt marshes. These valuable ecosystems hold vast carbon reservoirs; they sequester atmospheric CO2 through primary production, and then deposit it in their sediments. In fact, most blue carbon is found in the soils or sediments beneath the vegetation.

The rates of carbon sequestration and storage are comparable to (and often higher than) the sequestration rates in carbon-rich terrestrial ecosystems such as tropical rainforests or peatlands. Unlike most terrestrial systems, which reach soil carbon equilibrium within decades, deposition of carbon dioxide in coastal ecosystem sediment can continue over millennia. However, when these coastal ecosystems are degraded or destroyed they can become carbon dioxide sources due to the oxidization of biomass and organic soil.

Because coastal ecosystems do contain substantial amounts of carbon, and because this carbon is in danger of being released, they are important in mitigating climate change. Unfortunately, however, the rate of loss of mangroves, seagrasses and saltmarshes (driven mostly by human activities) is estimated to be among the highest of any ecosystem on the planet, prompting international interest in managing them more effectively for their carbon benefits.

Although the Avon Estuary’s contribution to carbon sequestration may be small on a planetary scale, that contribution strengthens the argument for its designation as a MCZ and for the inclusion of South Efford Marsh.



The Environment Agency (EA) responded to the community’s recent rejection of their revised plan for the flooding of South Efford Marsh (SEM) with a renewed drive to push ahead with the plan, in a probable collaboration with the Devon Wildlife Trust as managing partner.    The plan has now been elaborated in slightly more detail and can be read by clicking here – SEM – EA Summary of points051110 .    The area which the EA hopes to flood is depicted in the figure below, which shows the planned flood depth with salt water,  and in the diagram showing habitat type to be created and the proposed hide location (click here) proposed Habitat Creation .

The ACA’s committee has unanimously rejected these more detailed plans because much remains unclear.   The plans do not address our original  objections about a) the uncertain, wider environmental outcomes of the project  and b) the absurdity of destroying a well established BAP habitat (freshwater grazing marsh) to create a new one (salt marsh), over what might be a very extended period of time,  solely in order to meet a national EA target for new salt marsh creation.      Furthermore, the proposed freshwater ‘scrapes’ will be susceptible to ‘poaching’ by grazing cattle, unless fenced securely, and could become stagnant and unattractive to wildlife without a source of flowing fresh water. 

Gary Streeter MP and others are also very concerned about the waste of public funds at a time of cut-backs which will have widespread repercussions, some of which will include other environmental projects with, arguably, greater importance and urgency e.g. flood protection.

However, in a private meeting, Aveton Gifford Parish Council (in whose area the marsh lies) has now decided to welcome the latest scheme as a potentially attractive public amenity within their parish.  Whether this represents an acceptable level of public support for endorsement of the project is a moot point!   The PC did add the following caveats, as summarised below in italics :-

The proposal to proceed has a number of riders attached and was passed unanimously.
1) The aspect and consideration of Flood Risk by EA’s Development Control should include consultation with those Bridge End residents close to South Efford Marsh at road level and lower. We understand that there would be no increase in flood risk by flooding South Efford Marsh; and that particularly the most affected local resident should approve any additional work through walls and moats to help stabilise the risk to his property.
2) That the EA look at the current sewage arrangements for South Efford House. There is a licence for permitted discharge. The location of the current septic tank should be assessed. The need for different and renewed arrangements, bearing in mind the Planning Application for expansion should be reviewed.
3) The Parish Council, through their appointed representatives (say two people) wish to be included in the forward planning and decision making process to bring local knowledge to bear, and to add a liaison point for the project.
4) The Parish Council to be informed and approve the lease that is created with managing partners.

We can only hope that the Parish Council’s confidence in the scheme will be justified and that we shall not all be left with a lifeless sea of mud, or worse, for the foreseeable future.


The EA has responded to questions raised at an Aveton Gifford Parish Council meeting about the proposed flooding of South Efford Marsh with sea water  in the following document:- EA response to questions.

If you have any comments on these revised plans, prior to the public meeting on 17th September, why not start a discussion going on this website?