South East Strategic Regional Coastal Monitoring Programme

ANNUAL REPORT 2006

Dover Harbour to Beachy Head

AR19 October 2006 Cover photo: Early morning survey at Sowley, West Solent M. Wadey Annual Report 2006 Coastal Cell 4c: East /South

Canterbury City Council Strategic Monitoring Military Road Canterbury Kent CT1 1YW

Tel: 01227 862456 Fax: 01227 862537 e-mail: [email protected] Web Site: www.se-coastalgroup.org.uk www.channelcoast.org

Document Title: Annual Report 2006

Reference: AR 19

Status: Final Draft

Date: October 2006

Project Name: Strategic Regional Coastal Monitoring

Management Units: 4c MU1 – 4c MU26

Author: A. Spratt

Checked By C. Longmire

Approved By: S. McFarland

Issue Revision Description Authorised

01 Draft report for consultation

1 Annual Report 2006 Coastal Cell 4c: /South Kent Contents 1 Introduction...... 3 2 Condition of Management Units...... 6 3 Profile Change Summary ...... 12 4 Hydrodynamic Data...... 53 5 Topographic Analysis...... 59 5.1 ...... 59 5.1.1 MU1 (4c01787 - 4c01857)...... 59 5.1.2 MU2 (4c01723 - 4c01783)...... 59 5.2 Pevensey Bay...... 60 5.2.1 MU3 (4c01703 - 4c01722)...... 60 5.2.2 MU4 (4c01679 - 4c01702)...... 61 5.3 Bexhill...... 61 5.3.1 MU5 (4c01656 - 4c01672)...... 61 5.3.2 MU6 (4c01495 - 4c01565)...... 62 5.4. Hastings ...... 63 5.4.1 MU7 (4c01389 - 4c01490)...... 63 5.4.2 MU8 (4c01349 - 4c01382)...... 64 5.5 Fairlight...... 64 5.5.1 MU9 (4c01302 – 4c01324) ...... 64 5.5.2 MU10 (4c01275 – 4c01288) ...... 65 5.6 Pett Levels...... 65 5.6.1 MU12 (4c01156 - 4c01264)...... 65 5.6.2 MU13 (4c01061 - 4c01144)...... 66 5.7 Camber Sands ...... 66 5.7.1 MU14 (4c00949 – 4c01046) ...... 66 5.8 Romney Marshes ...... 67 5.8.1 MU16 (4c00770 - 4c00800)...... 67 5.8.2 MU17 (4c00617 - 4c00767)...... 67 5.8.3 MU18 (4c00444 - 4c00612)...... 68 5.9 Folkestone and Dover ...... 69 5.9.1 MU20 (4c00150 – 4c00346) ...... 69 5.9.2 MU22 (4c00097 – 4c00130) ...... 69 5.9.3 MU26 (4c00001 – 4c0060) ...... 70

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1 Introduction

The analysis within this annual report provides an overview of beach performance and wave and tidal measurements for coastal cell 4c (Beachy Head - Dover), using data collected over the last year from the strategic regional coastal monitoring programme. Topographic surveys are conducted at all viable sites using land based RTK GPS in the spring, summer and autumn of each year, covering pre-determined designated profiles at intervals along the coast. This report looks specifically at the difference between the latest survey set (Spring 2006) and the comparable data from Spring 2005.

All profile data was imported into SANDS® for analysis. This enables beach cross sectional areas (CSA) to be calculated as an indicator of beach quantity above and seaward of a master profile (Figure 1.1). Where available, seawalls are located spatially using a combination of design schematics and a sea defence survey conducted in 2003. The vertical level of master profiles are set close to the beach toe level or mean low water, whichever is deemed most appropriate. In some areas, clay levels have also been established using the results from trial holes dug into the beach. These have been incorporated to produce a more accurate master profile that calculates the actual beach area.

Seawall

GPS Profile

CSA

Master Profile

Figure 1.1 - Definition of Cross Sectional Area (CSA)

Data is presented at a number of scales, from an overview of the average change in each management unit, to changes and trends for each individual profile. The topographic analysis section of the report highlights notable changes and areas for concern for each of the management units. While this provides an accurate portrayal of current beach conditions and changes over the preceding year it should be stressed that these are only short-term trends calculated from specific data sets. In order to view the results in a meaningful light they should be compared with other data sets from each location.

Those areas that are designated beach management plan sites (Figure 1.2) benefit from a high-resolution beach plan survey every summer. These are utilised to produce a much more comprehensive beach analysis report and as such this report should be viewed as an interim update for those sites.

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.

Figure5 1.2 Annual Report 2006 Coastal Cell 4c: East Sussex/South Kent

2 Condition of Management Units To provide an overview of the annual change in each management unit, the average change in beach profile CSA is calculated for each unit. These averages are expressed in terms of percentage difference and actual change (m2) and are presented in Table 2.1.

Management Average CSA Average CSA No. of Profiles Unit Change (%) Change (m2) MU 1 21 -2.44 -5.26 MU 2 13 -0.76 -2.34 (Eastbourne) MU 2 14 -2.55 -10.35 (Pevensey) MU 3 20 0.17 1.61 MU 4 24 0.57 0.53 MU 5 18 2.05 3.15 MU 6 15 0.80 -8.08 MU 7 21 2.61 7.71 MU 8 11 -0.51 2.14 MU 9 3 7.59 8.17 MU 10 4 8.62 0.35 MU 11 - - - MU 12 24 3.38 3.43 MU 13 17 -2.23 -8.01 MU 14 23 0.89 4.41 MU 15 - - - MU 16 10 0.15 0.21 MU 17 51 1.59 2.19 MU 18 44 -9.01 -7.07 MU 19 - - - MU 20 53 0.18 -0.06 MU 21 - - - MU 22 8 4.22 1.01 MU 23 - - - MU 24 - - - MU 25 - - - MU 26 13 1.65 1.54 Table 2.1: Management Unit Beach Change Summary. Average CSA percentage and actual changes of greater than 5% magnitude are coloured pink/blue and red/green respectively.

These results are also illustrated as coloured thematic maps in Figures 2.1-2.3, with arrows representing the average erosion, accretion or no change for each unit. Arrows pointing out to sea represent accretion, whilst those pointing landward are indicative of erosion.

Most units demonstrate an average change of less than 5% CSA, considered to be within the possible effects of natural processes and survey error. It should be noted that the largest changes often result from units with very few profiles, where a single profile can skew the results. Although these figures can highlight a highly erosive unit, or a recent replenishment, they should be viewed with caution as, for example, it is possible to have a small highly erosive area within a unit that accretes material overall.

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Figure 2.4 shows the CSA change of individual profiles throughout the entirety of coastal cell 4c. Although profiles are not represented with respect to chainage from a start location, they are organised from right to left in sequential order from the most northeasterly at Dover to the most southwesterly profile at Eastbourne.

Caution should be given to detailed coastal examination based on these results alone as they reflect a short-term trend based on the state of the beach at two snapshots in time. These figures show overall trends, but individual profiles should be examined in more detail in those areas of interest. Crucially, the significance of any results should be put in context with previous fluctuations in beach CSA since the start of the monitoring programme in 2003.

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Fig8ure 2.1 Annual Report 2006 Coastal Cell 4c: East Sussex/South Kent

F9igure 2.2 Annual Report 2006 Coastal Cell 4c: East Sussex/South Kent

F10igure 2.3 Annual Report 2006 Coastal Cell 4c: East Sussex/South Kent

Figure 2.4 – CSA percentage change of all designated profiles in Unit 4c (Eastbourne – Dover), from Spring 2005 – Spring 2006 11 Annual Report 2006 Coastal Cell 4c: East Sussex/South Kent

3 Profile Change Summary Changes along individual profiles within each management unit are summarised in a series of thematic maps (Figures 3.2-3.42). The maps show the location and regional name of each beach profile, superimposed on aerial photographs taken in 2005. All profiles appear as 200m in length, though the distance over which CSA analysis is taken varies from profile to profile. Where possible, the annual change in cross- sectional area (CSA) has been calculated from Spring 2005 to Spring 2006.

Annex A contains two profile summary diagrams for each beach profile. The first is a plot of the 2006 spring survey including the master profile used for CSA analysis, and structures where available. The second is a graph plotting profile CSA values over time. Calculating CSA values for each survey allows a trend to be calculated that is considered representative of the neighbouring coastline and helps establish accretion/erosion trends. Anthropogenic interference, namely the introduction of shingle, artificial movement of material and the construction of controlling structures all affect these trends. As a consequence, trends are only calculated between engineering schemes, and replenishment activities are highlighted on the graphs. Where possible, historic data have been incorporated into the analysis (Figure 3.1).

1 3

2

Figure3.1 - Example of Beach Profile Trend Analysis

1. Beach Cross-Sectional Area (CSA) 2. Replenishment Activities 3. Mathematically Derived Trend line

A figure representing the mathematically derived trend (m2/year) is included in the summary sheets, in addition to the ‘actual’ change since the first project survey in 2003. These put into context the short-term trends that are displayed in the following thematic maps. Significant or unusual changes within a management unit are highlighted in the topographic analysis section of this report.

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4 Hydrodynamic Data

Pevensey Bay Wave Recorder

Location OS: 569358E 99118N WGS84: Latitude: 50°47'0.2''N Longitude: 00°25'1.5''E

Water Depth 9.8m CD

Instrument Type Datawell Directional WaveRider Buoy Mk III

Data Quality C1(%) Sample interval 98 30 minutes

Monthly Means All times GMT

Pevensey Bay - April 2005 to March 2006 H H T T Direction SST No. of Month s max p z (m) (m) (s) (s) (o) (oC) days April 0.495 0.765 5.7 3.5 188 8.6 30 May 0.633 0.987 5.3 3.5 179 11.5 31 June 0.524 0.813 5.1 3.3 175 14.9 30 July 0.552 0.857 4.7 3.3 190 17.2 31 August 0.472 0.734 4.8 3.3 189 18.3 31 September 0.545 0.846 5.6 3.4 184 18.6 30 October 0.836 1.309 5.2 3.7 171 16.4 31 November 0.834 1.306 5.6 3.7 182 13.3 30 December 0.824 1.288 6.3 3.9 180 9.3 31 January 0.867 1.353 5.6 3.8 161 6.9 31 February 0.791 1.231 6.2 3.7 161 5.6 28 March 0.901 1.408 5.5 3.8 168 5.2 31 Tables and plots of these values, together with the minimum and maximum values and the standard deviation are available on the website.

Highest events in 2005/6 Water level Tidal stage Tidal Tidal Max. * Date/Time Hs Tp Tz Dir. elevation (hours re. range surge* surge* (OD) HW) (m) (m) (m) 30-Dec-2005 3.55 7.7 6.2 176 1.25 HW -2 5.2 0.04 0.28 12:30 03-Dec-2005 3.55 7.7 6.1 201 3.15 HW 5.6 0.18 0.57 00:00 01-Dec-2005 3.37 7.7 6.0 173 2.88 HW 5.2 0.09 0.44 23:30 03-Nov-2005 3.14 8.3 6.1 217 1.46 HW +2 6.0 0.21 0.54

* Tidal information is obtained from the nearest recording tide gauge (the National Network gauge at Newhaven). The surge shown is the residual at the time of the highest Hs. The maximum tidal surge is the largest positive surge during the storm event.

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Highest events in 2005/6 Water level Tidal stage Tidal Tidal Max. * Date/Time Hs Tp Tz Dir. elevation (hours re. range surge* surge* (OD) HW) (m) (m) (m) 14:00 25-Oct-2005 2.94 7.7 5.5 211 1.42 HW 2.7 -0.15 0.12 04:00

Distribution plots The distribution of wave parameters is shown in the accompanying graphs of:

x Wave roses (Direction vs. Hs) for reporting year and all data x Percentage of occurrence of Hs, Tp, Tz and Direction from April 2005 to March 2006 x Monthly time series of significant wave height (the red line is the storm threshold) x Incidence of storms during the reporting period and all previous years. Storms are defined using the Peaks-over-Threshold method. The highest Hs of each storm is shown.

Summary The reporting year experienced less extreme storms than in the winter 2003/spring 2005 period (when the largest waves were measured since deployment of the Waverider), but the storms were concentrated in two distinct periods, each with an extended period of high waves. Late October/early November experienced a series of moderate storms, followed two weeks later by several days with waves around 3 metres. The late spring/summer and early autumn were generally quiescent. The highest storm waves were usually from the south and occurred either around or within 2 hours of High Water, on spring tides. Unlike the last reporting year, tidal surges of up to 0.5m were associated with several of the storms.

Acknowledgements Tidal data were supplied by the British Oceanographic Data Centre as part of the function of the National Tidal and Sea Level Facility, hosted by the Proudman Oceanographic Laboratory and funded by DEFRA and the Natural Environment Research Council.

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Direction vs. Hs as percentage of occurrence for July 2003 to March 2006 (all measured data)

Direction vs. Hs as percentage of occurrence for April 2005 to March 2006 (this reporting year)

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5 Topographic Analysis This section describes any significant changes that have taken place in each unit, highlighting any areas of concern, and putting the results in context with previous surveys. Where appropriate, plots of different surveys are overlaid and included to illustrate the changes described in the text.

5.1 Eastbourne

5.1.1 MU1 (4c01787 - 4c01857) This southwestern section of the Eastbourne frontage is slightly erosional, with only 4 profiles eroding and 1 accreting by more than 5% in the reporting period. In general, those profiles that erode do so without changes to the beach face gradient or profile shape. Instead, slight removal of material across the beach face appears to be the most common cause of CSA loss in MU1 (Figure 5.1.1). Figure 2.4 shows evidence of CSA percentage change increasing to the northeast, suggesting transport of material in a northeasterly direction from Holywell to Roselands. Previous beach management reports focused on this area substantiate this. As part of the capital recharge scheme of 1997/1998, alarm and crisis beach volumes were created, allowing an indication of beach performance relative to beach design conditions. There are inherent errors in converting design volumes to design profiles and CSA’s. Nevertheless, many profiles between 401787 and 4c01819 fall short of the critical CSA calculated from design volumes (see appendix for CSA time series graphs).

Figure 5.1.1 – Beach profiles at 4c1800 (left) and 4c1821 (right), Eastbourne, showing slight erosion of the beach face from spring 2005 to spring 2006.

5.1.2 MU2 (4c01723 - 4c01783) Sovereign Harbour separates the beaches contained within MU2, with beach recycling schemes transferring beach material from Langney point to the northeast of the harbour arms on a seasonal basis. A northeasterly longshore drift direction causes shingle to move towards Langney outfall, though the fairly constant CSA values to the west of this structure suggest beach material is still moving freely between groyne bays. The 4 groyne bays immediately east of the outfall marks the extraction site for beach recycling to Pevensey; the accretion shown here over the last year is likely to be a short term trend that will be

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reversed when recycling takes place in the future. The abrupt transition between this accretion dominant zone and the erosion downdrift of the harbour arm (which recycling schemes usually mask) is clear on Figure 2.4. To the southwest of Langney Point, the beach at Eastbourne is fairly stable, though recent erosion in front of the has caused the beach level to drop by approximately 0.5m and the berm to recede by some 2m in a year (Figure 5.1.2), causing the largest CSA decrease in this area. The section of beach to the northeast of the harbour arm within MU2 has suffered erosion from spring 2005 to spring 2006, although the ongoing management of this section of beach implies this erosion is not indicative of the predominant beach change. Figure 5.1.2 shows an example of erosion at profile 4c01727, typical of the beach changes here over the last year.

Figure 5.1.2 – Beach profiles at 4c01783 (, left) and 4c01727 (Sovereign Harbour, right) from spring 2005 to spring 2006. Although the erosion seen at the Redoubt appears part of a seasonally dynamic change in the beach shape, the erosion northeast of the harbour appears more consistently erosional, until the next beach recycling scheme increases beach levels here.

5.2 Pevensey Bay

5.2.1 MU3 (4c01703 - 4c01722) Although sections of MU2 were recycled within the reporting period, with the potential to influence the sediment budget of MU3 significantly, the only recycling schemes believed to have been undertaken by Pevensey Coastal Defence Limited in MU3 affected profile 4c01703 in the far northeast of the unit. This accounts for the 7% increase in CSA here. Most profile CSA changed by less than 5%, indicating the beaches stability over the past year. However, 2 sets of 2 adjacent profiles were more dynamic, at profiles 4c01721-2 and 4c01714-5. At both locations, the more southwestern of the 2 profiles eroded by at least the magnitude that the other accreted, suggesting that any material eroded has been transported with the prevailing northeasterly wave approach direction to the next profile. At profiles 401721 and 4c01722, the beach face appears to be becoming more vertical in shape. Erosion and accretion of material across the majority of the beach face was responsible for the CSA loss and accretion at the respective profiles (Figure 5.2.1). At profile 4c01715, the entire beach face eroded by as much as 0.8m vertically, with the formation of a beach crest at 4.5m OD forming at 4c01714 that raised the beach by as much as 1m in places. This suggests either human intervention of some kind has disrupted the beach, or a recycling

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scheme in the area has not been reported correctly. Overall, the profiles within MU3 show no obvious spatial trends, as regular recycling to Sovereign Harbour and this frontage ensures a fairly constant supply of material feeding the frontage.

Figure 5.2.1 – Beach profiles at 4c01715 ( left) and 4c01714 (right) surveyed from spring 2005 to spring 2006. Beach levels dropped by some 0.8m at 4c01715 over the reporting period, yet were raised at 4c01714. A recycling scheme currently not documented by the regional monitoring programme could be the cause. Much of the frontage, however, changed little between these survey dates.

5.2.2 MU4 (4c01679 - 4c01702) Management unit 4, which stretches from Beachlands, Pevensey, to Cooden, Bexhill, is a heavily managed beach with a complex seasonal recycling programme in place. This mechanical movement of material appears to correlate with the profile CSA changes seen along this frontage. As mentioned in the MU3 analysis, a recycling deposition site is the likely cause of accretion in the far southwestern section of MU4 (profile 4c01702). Adjacent to this, an extraction site stretching as far as profile 4c01698 explains the slight beach losses here. Beach material was added between profiles 4c01692 and 4c01694 over the last year, though only slight increases are seen between surveys. The two most erosive profiles in this management unit mark the boundaries of a large shingle extraction site, within which profile 4c01690 surprisingly accreted, possibly through the mechanical processes of extraction. CSA increases further east at profiles 4c01684-6 reflects the location of the final recycling deposition site in this unit.

The validity of the discussion at Pevensey heavily relies on the regional monitoring programme continually being informed and updated on recycling activities. Since the beaches of Pevensey (MU3-4) are heavily managed to a predefined profile/level, analysis of these management units is more a review of mechanical processes rather than natural shingle movement

5.3 Bexhill

5.3.1 MU5 (4c01656 - 4c01672) The densely groyned Bexhill frontage does not lend itself to regular recycling schemes. It is believed a small extraction of shingle from profile 4c01667 in the

61 Annual Report 2006 Coastal Cell 4c: East Sussex/South Kent far west of MU5 is the only mechanically derived beach change in the reporting period. This explains the slight CSA loss here and as far as 4c01658 that could have suffered from a lack of beach material feeding from the west. The central section of the frontage, as far as 4c01602, has a marked accretional trend despite no recorded recycling activity. The largest increase here occurs at profile 4c01632 that accreted because the berm has migrated seawards by some 10m in the last year, and similar accretion patterns occurred at other profiles though these were not as large (Figure 5.3.1). The origin of the material needed to cause such large topographic beach alterations is unclear, but it could originate from unsurveyed groyne bays, from below the reaches of the master profile used to calculate CSA, or from Pevensey Bay. Most profiles here are historically accretional (i.e. since 2003), yet rates over the last year have increased notably. Continuing east, the next 2 profiles (4c01591-9) both eroded by 8% CSA, with a 20-30cm vertical reduction over much of the beach face. CSA at these profiles are historically stable, thus this recent change is probably a short-term trend that will be reversed in the next year. The remaining 4 profiles in this frontage are slightly accretional though much inter-survey beach movement is evident from profile analysis, suggesting this trend may again reverse in the next reporting year. Indeed, an absence of terminal structures assists to make the beaches in MU5 particularly dynamic and prone to short-term changes, many of which were probably captured by the surveys used to calculate CSA changes in this report.

Figure 5.3.1 – Beach cross-sections from profile 4c01632, showing notable increases in berm width, and consequently CSA, from spring 2005 to spring 2006.

5.3.2 MU6 (4c01495 - 4c01565) The eastern half of MU6 is part of the site for a new rock revetment and beach replenishment scheme at Bulverhythe, which was completed in the summer of 2006. Although beach profile change is included in this report, no valid conclusions can be taken from this area as a few surveys would merely have captured sporadic changes in the beach during engineering work. The reader should be aware that, as part of the Bulverhythe scheme, profile positions and names will change in subsequent year’s analysis due to the repositioning of groyne fields and the revetment construction. The regional monitoring programme is awaiting a beach management plan report from Halcrow that will provide beach design conditions and groyne/revetment schematics.

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The CSA change in the remainder of MU6 can be split up into 3 distinct sections. In the west, profile CSA and beach shape changed very little from spring 2005 to spring 2006. The next 3 profiles east of this stable section all eroded by 10-11% CSA due to a narrowing of the beach berm and erosion of the beach face. All 3 profiles are currently on a downward CSA trend (Figure 5.3.2). The final profile before the capital scheme was the only profile to show accretion, particularly since summer 2005. A wider berm has formed over the last year, with the material removed from the profiles downdrift likely to be the source of this extra shingle. Additionally, some aspects of the Bulverhythe scheme nearby may have increased the ability of this section of the beach to trap material for longer durations.

Figure 5.3.2 – CSA history (autumn 2003 – spring 2006) and recent cross sectional beach change at profile 4c01543, Bexhill.

5.4. Hastings

5.4.1 MU7 (4c01389 - 4c01490) A capital beach scheme has recently been completed at Bulverhythe, causing recent topographic profile data to merely describe constantly changing beach levels as part of the works. Therefore, profiles 4c01463-1490 are not analysed within this report.

Immediately to the east of Bulverhythe, from profiles 4c01431-1455, there is no pattern to CSA changes; some profiles eroded, some accreted. In many cases, these changes were not inconsistent with trends of CSA taken since the monitoring programme began in 2003, suggesting this beach changes in different ways from groyne bay to groyne bay. The next 4 profiles all eroded, 3 of them by more than 5%. This was due to the erosion of the highest beach crest, with only slight accretion further down the beach (Figure 5.4.1). The shape of the sea wall and promenade here means the beach is comparatively narrow and would be more likely to erode. The final 5 profiles before Hastings pier generally accreted, 2 greater than 5% in the reporting period. The proximity of the pier could be affecting beach movement here, though the fairly constant CSA trend of most profiles indicates this change may be a short-term increase in beach area.

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Figure 5.4.1 – Beach profile surveys from 4c01415, Hastings, showing beach change from spring 2005 to spring 2006.

5.4.2 MU8 (4c01349 - 4c01382) MU8, stretching from the pier to East Hill, Hastings, possessed little profile CSA change in the last year. Only two profiles changed by more than 5% CSA, with most showing slightly accretional tendencies. An exception to this is in the west of the frontage, where the losses seen from spring 2005 to spring 2006 at profiles 4c01376-1382 reflect an ongoing erosional trend. The remainder of the frontage is historically stable or slightly accretional (Figure 5.4.2).

Figure 5.4.2 – Comparison of typical profile CSA trends from the far west of MU8 (left, 4c01382) and the east of MU8 (right, 4c01365)

5.5 Fairlight

5.5.1 MU9 (4c01302 – 4c01324) Only 3 designated profiles exist within a small section in the west of MU9, therefore substantial conclusions of beach movement are difficult to make. However, the recent increases at profiles 4c01314 and 4c01302, caused by accretion across the beach face but not the foreshore, are set against previous losses in CSA, suggesting this accretion could reverse in the following year. The

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small CSA loss at profile 4c01324 is unsurprising given this profiles stability over recent years.

5.5.2 MU10 (4c01275 – 4c01288) Only the eastern half of Fairlight Cove contains profiles surveyed by the monitoring programme. Profile 4c01288, which does not front the rock revetment in this management unit, accreted by 5% CSA due to accretion above 3m OD, possibly due to erosion and transport of the landslide at Rockmead Road to the southwest. Profile 4c01279 and 4c01283 both eroded due to a lowering of the beach face, though the beach berms remained stable. A large percentage increase at profile 4c01275 was caused by a 20-40cm vertical increase in the level of the beach seaward of the rock revetment, though the short length of the profile used to calculate CSA resulted in such a large CSA percentage increase. It seems possible that the revetment is gradually trapping beach material towards its northeastern end. Despite short-term changes to beach shape and level, the profiles within MU10 have remained fairly stable since the monitoring programme began.

5.6 Pett Levels

5.6.1 MU12 (4c01156 - 4c01264) The beaches south of Winchelsea and Rye undergo recycling whereby shingle is excavated from the terminal groyne at Rye Harbour (MU13) and deposited into the groyne bays in the western end of MU12. The 4 most westerly profiles also lie within a capital coastal defence scheme, due for completion in 2010.

Profiles 4c01242-1264 have all accreted over the reporting period, predominantly due to recycling and gradual recharge of the new groyne bays. The highest CSA percentage increase, of 81%, at 4c01242 was due to the beach elevation increasing by as much as 1.5m in places. The other 3 accreting profiles all showed elevation increases over the beach face.

The next four profiles to the northeast, which fall outside the capital scheme boundaries, all eroded over the last year, and have been historically eroding since the monitoring programme began. Although the beach berms here are fairly stable, the lowering of the beach face is causing a steepening of the beach that would increase the chances of the berm being undercut in the future (Figure 5.6.1).

The remainder of this management unit experienced little CSA change from spring 2005 to spring 2006, with the exception of 3 sporadic profiles that changed by more than 5%. Profiles 4c01180 and 4c01202 both accreted, the former due to continued gradual accretion since 2003, and the latter due to a significant 5m increase in beach berm width, and a 0.5-1.0m vertical increase in beach face levels. Such notable changes suggest a recycling operation, though none have been recorded at the time of writing. A recycling operation could also be to blame for reductions in beach levels at profile 4c01162, where the berm has receded by some 4m over the winter of 2005/2006, causing the 14% CSA loss over the last year.

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Figure 5.6.1 –The gradual landward migration of the beach face at profile 4c01239 (right) has caused a steepening of the beach profile, which might soon result in the currently stable berm retreating as well.

5.6.2 MU13 (4c01061 - 4c01144) MU13 stretches from Winchelsea Beach in the west to Rye Harbour in the east. The terminal groyne that protects the entrance to the harbour acts as a shingle trap, which in turn is recycled back to the western end of MU12.

In general, profile CSA within the unit changed very little. Most profiles have been uninfluenced by any recycling schemes and receive a natural supply of shingle from MU12. This is apart from the most easterly profile, located in the middle of the extraction site, which eroded by 34% in a year due to the recycling scheme mentioned above.

5.7 Camber Sands

5.7.1 MU14 (4c00949 – 4c01046) Lydd Ranges (MU15) experiences a recycling programme where material taken from the Dungeness peninsula is deposited as far east as Jury’s Gap. This explains the CSA gain at profiles 4c00949 and 4c00952 caused by an increase in berm width and beach face accretion.

The remainder of MU14 was much less changeable from spring 2005 to spring 2006. From the Rye Harbour entrance to profile 4c01015, little CSA change occurred, despite the terminal groyne at the harbour arguably preventing natural sediment movement into the unit. Indeed, most profiles in this western section have been very stable since 2003, changing by only a few tens of centimetres in level. The remainder of the unit is more dynamic, with 2 profiles eroding and 2 accreting by more than 5% in the last year. Analysis of the profiles shows that although there is some movement of the beach face, this is insignificant compared with beach elevation changes at, and seaward, of the beach toe, which changes height notably between surveys (Figure 5.7.1).

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Figure 5.7.1 – Spring 2005 and spring 2006 surveys from profile 4c00977

5.8 Romney Marshes

5.8.1 MU16 (4c00770 - 4c00800) An annual recycling scheme by the EA/Halcrow moves shingle from the eastern side of the Ness peninsula (far south of MU17) to the MU16 frontage. The last documented recycle was completed just before the spring 2005 surveys were completed, therefore the analysis within this report is indicative of the beaches response to natural processes only. Encouragingly, the profiles suggest the beach has remained very stable, with no profile CSA changing by more than 5%. SANDS suggests that the profile CSA trends here have also been very stable over the reporting period (note the stability/linearity of profiles trends here from spring 2005-spring 2006 in the appendix). Unfortunately, no design profiles are available for this frontage. However, the beach appears to be performing well after the last recharge a year ago, as the overall beach profile has changed little in berm width/beach face gradient, and CSA has remained fairly constant.

5.8.2 MU17 (4c00617 - 4c00767) The 8.5km MU17 frontage extends from Dungeness to Littlestone-on-Sea, and was influenced by a recycling scheme that removed some 38,000m³ of shingle shortly before the spring 2006 surveys were completed. An area bounded by profiles 4c00752 and 4c00767 marked the extent of the shingle extraction, which was used to recharge the Lydd ranges frontage (MU15).

Profile changes in MU17 can be generalised into 3 sections over the last year. In the south of the management unit, erosion has been dominant in the last year. To the north and as far as Lydd-on-Sea, profile CSAs have remained fairly stable or accreted. As mentioned, the extraction of shingle from the south of the unit is the principal cause of CSA loss, with some sections of the beach face dropping by as much as 2m from the pre-recycling levels (Figure 5.8.2). To the north, accretion occurs due to the dominant northerly longshore drift direction along this frontage. The increases in CSA could be larger if regular recycling was not carried out in the south of MU17, as the sediment budget in MU17 is artificially reduced each year. However, profile CSAs have remained stable or accretionary in this middle section of the MU17 frontage suggesting there is enough drift of material from the south to maintain current beach levels. To the north of Lydd-on-Sea, beach CSA has remained relatively unchanged, with only 5 profiles changing by more than

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5% CSA from the 28 profiles in this section. Occasionally, short-term changes to dynamic profiles has caused a CSA change over 5%, though most profiles suggest the beach is stable here.

Figure 5.8.2 – Spring profiles from 2005 and 2006 showing changes in beach elevations caused by a recycling extraction site at this location.

5.8.3 MU18 (4c00444 - 4c00612) MU18 stretches from Littlestone-on-Sea in the south to Redoubt in the north. This frontage has undergone two major capital engineering works since the regional monitoring programme began. A beach replenishment scheme completed in the summer of 2003 added 250,000m³ of shingle between Littlestone-on-Sea and St. Mary’s Bay. Work is continuing on a rock revetment in the far north of the unit, and profile analysis will not be included in this report for this area given the absence of any topographic data collected here over the last year.

Beach performance of the area replenished in 2003 can be estimated as critical berm widths were provided as part of a BMP report by Jacobs Babtie (2005). The project is awaiting an update to SANDS that will allow these critical beach levels to be displayed graphically as part of the CSA graphs included within the appendix of this report. 2 profiles (4c00554 and 4c00592) are currently below the documented critical levels, and most profiles have been eroding gradually since the replenishment scheme was completed. This is well reflected by the profile CSA percentage change that ranges from +1% to –9%. To the north of St. Mary’s Bay, a section containing 26 profiles, only 4 profiles did not erode by more than 5% CSA in the reporting period. Notably, this section of MU18 had the most consistently erosional trends of any management unit in the East Sussex/South Kent region (Figure 2.4). Profile surveys indicate this is due to considerable loss of beach material between October 2005 and February 2006 (2 storms in this winter were above the storm threshold at Folkestone), and although some profiles have recovered slightly from a marked reduction in CSA, they remain at comparatively low levels. A vertical lowering of 0.5-1.0m was commonly seen over this period (Figure 5.8.3), with no recycling activities recorded at the time of writing.

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Figure 5.8.3 – Change in elevation at profile 4c00464 (near Dymchurch) between autumn 2005 and spring 2006. Note the notable reduction in already low beach levels at this site. Such losses were representative of much of the beaches between St. Mary’s Bay and Willop Basin.

5.9 Folkestone and Dover

5.9.1 MU20 (4c00150 – 4c00346) The Hythe to Folkestone harbour frontage has undergone a complex series of recycling schemes in the last year, causing many areas of the beach to have been influenced by anthropogenic forces. 3 large groyne bays in the western half of the frontage all experienced a similar recycling pattern over the last year, where material was transferred from the far east to the far west of each individual groyne bay. This allows recycled shingle to drift through the frontage with the prevailing westerly longshore drift direction. CSA change corresponds well with the documented extraction and deposition sites, as the most westerly profile in each bay accreted and the most easterly eroded. Most profiles away from the groyne structures are fairly stable suggesting that the extra drift of sediment through the bay is sustaining beach levels effectively. The groyne bay that encapsulates Sandgate is documented as having only an input of shingle through recycling. Profile CSA trends are generally accretional since 2003 and have been fairly linear over the last year; only profile 4c00256 eroded by more than 5% but has since recovered.

The 3 comparatively narrow groyne bays at Mill Point were much more variable, predominantly due to recycling activities. Alarmingly, profiles 4c00175A- 4c00177A and 4c00181A-4c00183A all eroded significantly over the last year, despite an input of shingle to the latter 2 profiles in the winter of 2005. This negative change in CSA is perhaps exacerbated, however, by exceedingly low beach levels during the spring 2006 survey that had improved by summer 2006. The remainder of the frontage, from profiles 4c00150-4c00172, changed little over the reporting period.

5.9.2 MU22 (4c00097 – 4c00130) Some areas of the 3km Folkestone Warren frontage possess very low beach levels. This means relatively small changes in beach topography result in large CSA percentage changes. In the west of MU22, profiles 4c00122-130 have not

69 Annual Report 2006 Coastal Cell 4c: East Sussex/South Kent experienced much change in the last year and have been fairly stable historically. Profile 4c00108 can be summarised in the same way. However, the remaining profiles are located over very low beach levels. Consequently, these profiles show very dynamic CSA trends over time, as a relatively small elevation change can lead to percentage CSA changes of 50% year on year. Perhaps a more useful observation from the beach surveys here is that the spring 2006 CSA at all profiles other than 4c00099 are the lowest since the monitoring programme began.

5.9.3 MU26 (4c00001 – 4c0060) The two 1.2km long beaches to the west and east of the Western Docks, Dover, have remained fairly stable since the monitoring programme began. In general, the maximum vertical range of the beach face over the last 3 years is approximately 1.5m, though movement in the last year has been much less (Figure 5.9.3). The slightly accretional pattern of profile CSA to the west of the docks was caused by the spring 2005 survey picking up low beach levels, which recovered over the reporting period. To the east of the docks, profile form or CSA has been comparatively stable. Profile 4c00001 accreted over the reporting period despite continuing a slight downward CSA trend, which could indicate erosion close to the eastern docks.

Figure 5.9.3 – Position of the beach as surveyed in autumn 2003 at profile 4c00019, with the range of subsequent survey elevations up to spring 2006 bounded by the dotted green lines. Note the range of beach levels is fairly small in this sheltered area, and this small CSA change pattern is repeated through most of MU26.

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