see previous F-2020-0011

First Coastal Corporation, Post Office Box 1212, 4 Arthur Street, Westhampton Beach, NY 11978 Phone: 631-288-2271, Fax: 631-288-8949 www.firstcoastal.net

Environmental Consulting and Construction. Permits to Construction. Preserving the coast since 1975

Friday, August 27, 2021 Hannah Willey Coastal Process Engineer, NYS DOS 41 State Street Albany, NY 12231-0001 Attn: Consistency Review RE: Thomas Gahan – Low-Sill Bulkhead Permit Application 23 Shore Road, Westhampton Beach NY Re: F-2021-0510 Dear Ms. Willey: Thank you for your letter of August 04, 2021. Please see our responses to your request for additional information below.

• The Creek fronting the subject property was dredged to create a canal suitable for small vessel navigation. The shoreline at the subject property is suffering from continued undercutting of the bank and slumping of the shoreline due to slope readjustment from the past dredging. The slope of the canal bank is greater than the angle of repose. Thus, slope readjustment through slumping in ongoing.

• No fill landward of the proposed sill is needed as we have revised the project plans so that the proposed sill has been moved landward towards the applicant’s property and flush with the existing slope to the greatest degree practicable. The sill is stable because is a cantilevered design with 50% plus 1 foot of the sill below the lowest grade, and with piles on landward side of the sheathing. The longest fetch across the waterway (perpendicular to the proposed sill) is approximately 80 ft at mean low water, providing low wave energy site conditions year-round. Wave energy generated by small vessel traffic will not endanger the structure of the proposed sill.

• Alternatives to the proposed low sill:

1. Vegetation only. The shoreline is presently well vegetated with native species. The vegetation, however, has been insufficient to stabilize the bank due to continuous slope readjustment due it’s steep angle.

First Coastal Corporation, Post Office Box 1212, 4 Arthur Street, Westhampton Beach, NY 11978 Phone: 631-288-2271, Fax: 631-288-8949 www.firstcoastal.net

Environmental Consulting and Construction. Permits to Construction. Preserving the coast since 1975

2. Coir logs. The use of coir logs at the site is impeded by the ongoing

slope readjustment that is caused by the prior dredging of the Creek to form the Canal.

3. Rock sill / Oyster reef. The subject canal is too narrow (± 80 ft wide) for either a rock sill or oyster reef. The placement of rock/oyster sill would occupy all of the space needed for safe and accepted navigation. The necessary base of a trapezoidal rock sill or oyster shell reef would occupy a much greater footprint (approximately 12’) than the proposed low sill and would obstruct navigation of the canal. The ACOE standards mandate that structure may not extend more than 25% of the width of the waterway (canal) as measured at mean low water. The canal width of 80’ leaves 12’ for structures, including docks. The rock/oyster sill would preclude the use of the dock which is a riparian right.

4. A low sill bulkhead with Spartina plantings is the most effective

manner to (a) preserve the upland, (b) encourage stable Spartina marsh growth, and (c) minimize the footprint of the stabilizing structure on a narrow canal.

• The dock at the property has existed in its current location and configuration

since at least 1978 as evidenced by the enclosed Suffolk County GIS aerial photograph.

If you have any questions or need additional information, please feel free to contact me. Sincerely, First Coastal

ANDREW H. Baird Permit Administrator 631-288-2271 x5# andrew@firstcoastal.com

Sketch No. 2: Guidance on length of structures in linear waterways.

8. A maximum intrusion into a waterway in areas where there is not a physical width constriction is alsodesirable to preclude excessive loss of public water usage. In general, new structures should conform inlength to adjacent structures and customary usage of the surrounding area. In areas where existingstructures and usage do not seem applicable, a reasonable maximum authorized distance beyond meanlow water of 600 feet (the traditional cable length) will be used. This may be modified if necessary forsite specific conditions or public benefit (see sketch no. 3).

Sketch No. 3: Guidance on spacing structures relative to adjacent properties andmaximum length beyond mean low water (MLW).

July 1996, discard previous editions

Source: USACE Guidelines“For the placement of fixed and floating structuresin navigable waters of the United States”

HOUSE

PATIO

PATIOSPA

POOL

PERVIOUS DRIVE

SHORE ROAD

ONECK TERRACE

ONECKCREEK

GARAGE

FLOAT

SLATERAMP

STON

EW

ALL

LANDWARD LIMITOF TIDAL WETLANDS

MHWMLW

LANDWARD LIMITOF TIDAL WETLANDS

PROPOSED LOW-SILLBULKHEAD APPROX. 295'

DOCK

56'

73'

88'

44'

24'

2.5 ft

MHW

MLW

MARSH

EROSION ESCARPMENT

6" x 6" DIA. PILE

PVC SHEETING

BOLTSTWL

CROSS SECTION A - A1

SCALE 1" = 2'

PROPOSED LOW-SILLBULKHEAD APPROX. 295'

NOTE: UNTREATED WOODONLY TO BE USED

(E.G. IPE OR OTHERTROPICAL HARDWOOD)

EXAMPLE OF LOW-SILL BULKHEAD [REMSENBURG NY]

5'

5'

AA1

PLANT SPARTINA GRASS 12" O.C.AS NEEDED

NO FILL IS PROPOSED

REVISIONS DATE

Date: Drawn By:

Drawing No.:

Sheet No:AHB

SCALE:

P.O. Box 1212, 4 Arthur StreetWesthampton Beach, N.Y. 11978(631)288-2271; fax (631)288-8949

1" = 40'

1 0F 1LS-BULKHEAD-A

05/06/21

GAHAN PROPERTY23 SHORE ROAD

WESTHAMPTON BEACH NY 11978SCTM # 0905-009-02-01

AMEND FOR NY DOS 08-25-21

1978 AERIAL PHOTOGRAPH - SUFFOLK COUNTY GIS VIEWER

DOCK AT SUBJECT PROPERTY

REVISIONS DATE

Date: Drawn By:

Drawing No.:

Sheet No:AHB

SCALE:

P.O. Box 1212, 4 Arthur StreetWesthampton Beach, N.Y. 11978(631)288-2271; fax (631)288-8949

1 0F 1Photographs-B

08/23/21

GAHAN PROPERTY23 SHORE ROAD

WESTHAMPTON BEACH NY 11978SCTM # 0905-009-02-01