The Making of a Gravel Beach (Cavo, Elba Island, Italy)

P2, L80-85 Be more precise what is the goal of the paper than just “Results are of general interest…”. Is the main goal of the paper to show under which conditions is the gravel beach volume stable? Then add context to sections 5.1, 5.2, 5.3 and 7 that follow the main goal of the paper. E.g. how does grain size change the gravel beach volume stability?

We specified those who are interested in the results and why.

In 5.1 we give more information on goals and results.

P2, L50-L60 Is there some other option on the Elba island? E.g. gravel excavated from rivers. Please comment.

We explain that there are not river plains on the island, and riverbed quarrying is prohibited in Tuscany (also because it’s one of the causes of beach erosion)

P2, L70-L71 Please add a one-line description why the first restoration attempt in 1999 was not successful for fluidity. The reader is immediately interested about the first attempt.

We better explained this

P6, L162 “sensible” should be “sensitive”

Corrected

P9, L230-235 As the one of the main objectives of the paper is to show how the beach is stable and resilient to beach erosion, more attention should be given to waves. Waves should be the main beach erosion driver. If the beach is oriented to the mainland as stated in this paragraph, the authors should give more information regarding fetch size, statistical data regarding wind magnitude and direction, as most wave are probably wind waves. Maybe use CMEMS wave model data to present order of magnitude values.

We added information on fetch and waves. We also give tidal range value, which cannot trigger significant tidal currents. WWA data were used

P11, L287 delete the word “follow”

Done

P14, L353-L355 Please comment why is there no coarse sediment offshore the 2 m isobath.

This is one of the main results explaining why gravel nourishment are stable: we do not loose sediment offshore. Unfortunately, there are few studies on mixed sediment beaches not limiting the analysis at the dry beach. Some papers are quoted, both for natural and nourished beaches.

 P17, L392-L394 “but” is a strange connector for this context, maybe “thus” or “therefore” would be more appropriate, or simply “and”

Modified the sentence.

Ref. 2 Comments and Suggestions for Authors

The thank the reviewer for the useful comments. We tried to solve the highlighted problems. 

Figures and units should be explained better. Prefer mm instead of phi or Mz.  Reference to figures and explanation should be improved

A logarithmic scale is preferred in coastal studies because fall velocity is not linearly linked to grain size (1.0 mm and 2.0 mm grains behave differently, but 100,0 and 100,1 behave in the same way, even if the difference is 1 mm in both the cases). However, in the text we add values in mm to those in phi.

More information is appreciated on wind, current and wave conditions at the beach. What is tidal range, mean and extreme wave height, water velocity tidal currents. 

More information should be provided on the methods that were used to apply the gravel nourishments. 

We added information on how the project was executed.

Ref. 2 Notes on the text

We thank the Reviewer for the careful reading of the text and for the language corrections. Actually, several points were not very clear. We made almost all the conceptual and language corrections he suggested. Here we put some comments to explain the most important one, or the very few for which we prefer the original form.

L. 96 So land degradation and erosion was stopped, that seems beneficial?

Yes, it is so for those living inland, but for all those that abandoned agriculture to move to the coast to work on tourism, it is not so.

L. 105 But than you would expect accretion at the other side?

The updrift beach expanded a little, but it’s not the urban beach, which has a higher tourist value. We explain this now.

L 134. How is shoreline defined? Waves? Tide? Wind?

The shoreline is the zero isobath/isohypse (contour line). Its position is independent from waves and tide. We think that only if other datum is used (instant water line, litter line, wet sand line) explanation should be given.

L. 212 Pleas explain Folk & Ward parameters.

We added the year of publication (1958) of Folk & Ward paper ‘Brazos River bar [Texas]; a study in the significance of grain size parameters’. These parameters are those used in almost all the sedimentological studies (it has 9678 citation following Google Scholar, i.e. excluding all the papers published before electronic references are used).

Fig. 12 Please explain (give titles) to horizontal and vertical axes and explain phi and Mz

The present caption ‘Mean size (phi) vs. Depth (m) for the sediments’ with the horizontal axes labelled (phi) and vertical axes labelled (m) explains what reviewer asks.