State of Maine's Beaches in 2011

Goose Rocks Beach, Kennebunkport

A total of four beach profiles (GR01 to GR04, Figure 44) were available for comparison. The profiles are spread along the beach, from southwest near the Batson River, to the northeast, near the Little River. It is important to note that all starting stakes were lost in the storm; however, new stakes were established by volunteers in approximate previous locations. In addition, volunteers have noted that the starting pins for profiles at GR03 and GR04 have been moved several times in late 2009 and 2010, so data may be flawed.

Winter Profile Changes

GR01 = A (95)

Figure 45

This profile is located adjacent to the Batson River, at the southwest end of the beach. Profile GR01 received a B- in the last assessment. The post-storm profile underwent apparent recovery by 2008 (Figure 45), with the formation of a berm and numerous swash bars, which dramatically raised the elevation of the upper portion of the profile, and along most of the remainder of the profile. In 2009, the upper portion of the profile continued to grow, while the low-tide portion of the profile lost elevation below the 2008 profile shape. By 2010, the same trend continued, but the low-tide area actually eroded to below the 2007 profile shape, starting at about 100 m from the pin. In 2011, the profile recovered well, with the low-tide elevation gaining sediment. This profile has recovered well with continued berm and dune growth. It reflects the dynamic migratory nature of swash bars at the Batson River, and will likely continue to show dramatic changes in the berm and low-tide swash bars.

GR02 = B (85)

Figure 46

GR02 is located at the central portion of the beach, in the southern cell along Goose Rocks Beach. Profile GR02 received an A in the last assessment. By 2008 (Figure 46) the profile exhibited excellent recovery, with the development of a well-defined berm. Recovery continued in 2009, with additional berm growth and elevation gains in the low-tide portion of the profile. The 2010 profile exhibited more elevation growth in the low-tide area. In 2011, growth occurred in the berm, while the low-tide portion of the profile lost some elevation, but stayed above the 2008 and 2009 profile elevations. This profile appears to be continuing to recover very well, and has undergone good growth since 2007.

GR03 = C- (72)

Figure 47

GR03 is located in the northern third of the beach, within a cove between the Little River and a salient formed by offshore outcrops. Profile GR03 received a C- in the last assessment. The beach recovered well by 2008 (Figure 47), with the profile developing a well-defined berm, and elevation increase along the length of the profile. However, the profile was eroded by April 2009. A high berm remained, but the offshore portion of the profile was at elevations below the 2007 post-storm profile. This trend continued in the 2010 beach shape, which was lower in elevation than the 2009 shape. Unfortunately, the 2011 shape showed more erosion of the dune crest, and only a small, poorly-defined berm. However, the profile elevation did not lower any more than the 2010 level, indicating some stability. Still, this profile is showing steady erosion since 2008.

GR04 = A (95)

Figure 48

GR04 is adjacent to the inlet of the Little River, at the northeast end of the beach. The profile received a B in the last assessment. The beach profile exhibited dramatic recovery in 2008 (Figure 48), with extensive elevation gains, especially seaward of the 50 m mark. In 2009, the upper portion of the profile increased in elevation substantially, by over 1 meter; however, the offshore portion (seaward of 50 m) of the profile decreased in elevation along its entire length. By 2010, the profile underwent intense erosion along its landward section, with about a 1.5 meter decrease in elevation. From about 50 m seaward (the low-tide swash platform), the profile increased in elevation. In April 2011, the entire profile had gained substantial amounts of sand, on average about 75-100 cm. The variability of this profile lends itself to proximity to the Little River and the dynamic low-tide swash platform, which receives migrating sand bars, periodically resulting in accretion or erosion. In its current trend, this profile represents marked recovery and accretion.

Winter Beach Grade = B (87)

Interestingly, the winter profiles at Goose Rocks Beach show good shapes and good scores. One typically expects profiles to fair worse in winter than in summer. It is clear that the proximity to the rivers of GR01 and GR04 lend themselves to protection. Also, it appears that shoals (ebb-tidal deltas) from the rivers more positively influence the profiles in winter.

Summer Profile Changes

GR01 = C (75)

Figure 49

The summer 2007 (Figure 49) post-storm profile had a dune crest, and a relatively steep slope to a wide, variable low-tide terrace, with what appeared to be a large bar at the 100 m mark. By 2008, the dune crest appears to have eroded landward slightly, and the bar migrated up the profile, with a series of offshore bars moving up the profile, the dune crest recovered, but the nearshore portion of the profile, at the 100 m mark, substantially lowered, and the offshore bars appear slightly smaller than in 2009. In the summer of 2010, the profile showed some dune erosion, and little changes seaward. This profile, in terms of its summer shape, appears to be slowly migrating landward at the dune crest and nearshore portions. It also shows dynamic changes due to the influence of the Batson River and associated swash bars, which cause episodic erosion and accretion. Overall, however, it appears generally stable and we remain cautiously optimistic.

GR02 = B (85)

Figure 50

By summer of 2007 (Figure 50), the profile displayed a wide, well-defined berm, and slope to the low-tide area. Within a year, the berm had flattened and gained in elevation out to about 40 m, where the break in slope occurred. In the summer of 2009, the wide, well-defined berm so evident in 2007 and 2008 disappeared. The entire profile flattened and the slope decreased, however the elevation of the most landward portion of the profile increased. By 2010, the well-defined berm had returned, maintaining its position and break in slope, but increasing slightly in elevation. The summer beach at this location appears to have maintained a good, well-defined berm over the past few years, and has generally increased in elevation since the post-2007 storm profile. This may be due to the sheltering of the cove by offshore bedrock outcrops.

GR03 = D (65)

Figure 51

In the summer after the 2007 storm (Figure 51), the summer profile had a steep slope off the dune, and a defined berm, which gently sloped offshore to the low-tide area. By 2008, the profile appears to have eroded landward, with decrease in the dune, berm, and the formation of a much steeper slope to the low-tide area. The profile recovered very well by summer 2009, with a large gain in elevation at the berm, and a return to a relatively gentle slope to the low-tide area. However, in summer 2010, the profile was massively eroded, losing over 1 m of elevation near the 40 m mark in comparison with the 2009 profile. In fact, the profile was eroded down to elevations below that of the 2008 or 2007 post-storm summer shapes. Although the profile showed good initial recovery into 2009, because of its poor performance in 2010, we remain highly cautious and give the profile a "D". Further monitoring and comparison with summer 2011 shapes is required; we also note that the profile starting point has changed several times, according to volunteers, which may impact this assessment.

GR04 = D (65)

Figure 52

Although GR04 (Figure 52) underwent very good recovery in terms of its winter shape, its summer shape appears to be suffering from intense short-term erosion. After some increased erosion in 2008, the profile rebounded dramatically in 2009, gaining nearly 1.5 m in elevation at the 100 m mark. (Note: we feel the 3 extremely high points recorded in 2009 are erroneous.) However, in the summer of 2010, the profile underwent massive erosion, lowering by over 3 m at the 100 m mark. Although this profile clearly underwent massive erosion in the summer of 2010, because of the highly variable nature of this profile due to its proximity to the river and its dependence upon the dynamic low-tide swash platform and overall retention of sand within Goosefare Bay, we do expect this profile to recover by the summer of 2011. At the same time, due to its dynamic nature, we do expect it to undergo highly variable changes (both massive erosion and accretion) in the future. Comparison with the summer 2011 shape will help determine if recovery has occurred. Because of the short-term nature of the erosive trend (2009-2010), we assign this profile a "D" instead of an "F". We also note that the profile starting point has changed several times, according to volunteers, which may impact this assessment.

Summer Beach Grade = C (73)

It appears that the summer profiles at Goose Rocks Beach are not fairing that well, aside from GR02. The profiles at the northern end of the beach, GR03 and GR04, appear to be undergoing summer erosion, especially from 2009 through 2010. Comparison with summer 2011 profiles is needed.

Summary

At Goose Rocks Beach, there continues to be dramatic variation in profile shapes at the end members (GR01 and GR04) due to influence of the adjacent rivers and shifting sand bars on their ebb-tidal deltas, especially during the summer months. The highly variable profiles at GR01 and GRO4 appear to have massive swings in terms of their profile shapes from year to year. These profiles appear to be fairing relatively well during the winter, yet remaining highly variable in the summer. The most stable profile at the beach appears to be GR02, which is quite protected by offshore bedrock outcrops. Part of the variability may be due to the fact that the profile starting points have varied due to loss of starting pin locations at GR03 and GR04, as noted by volunteers. The setting of newer, more permanent starting pins would aid in future analysis.

Overall grade = B- (80)

Contents Introduction Beach Responses Discussion Conclusions References Appendix

Last updated on July 14, 2011