Galveston coastal fieldwork

Task question:

http://www.houstonchronicle.com/news/houston-texas/houston/article/Sea-swallowing-Galveston-faster-than-thought-4160081.php

Source:http://blog.galveston.com/wp-content/uploads/2013/05/seaweed.pdf

The West End of the Island is eroding

The East end of the Island is getting bigger

The Seawall was built after the 1900 hurricane. It is 10 miles long.

Coastal protection: Galveston sea wall

Coastal protection: Galveston sea wall

• The Galveston Seawall was built after the Galveston Hurricane of 1900 for protection from future hurricanes. Construction began in September, 1902, and the initial segment was completed on July 29, 1904. From 1904 to 1963, the seawall was extended from 3.3 miles (5.3 km) to over 10 miles (16 km) long.

• Reporting in the aftermath of the 1983 Hurricane Alicia, the Corps of Engineers estimated that $100 million in damage was avoided because of the seawall. On September 13, 2008 Hurricane Ike's storm surge and large waves over-topped the seawall. As a result, a commission was established by the Texas Governor following the hurricane to investigate preparing for and mitigating future disasters.[4]

Other forms of coastal protection at Galveston

• Riprap — also known as rip rap, rubble, shot rock, rock armour or Rip-rap — is rock or other material used to armor shorelines, streambeds, bridge abutments, pilings and other shoreline structures against scour, water or ice erosion.

Crews replacing riprap at Galveston Seawall after 1915 Hurricane

Groynes at Galveston

Why is this house like this?

Hurricane proof houses

• Dome: The physical geometry of a building affects its aerodynamic properties and how well it can withstand a storm. Geodesic dome roofs or buildings have low drag coefficients and can withstand higher wind forces than a square building of the same area.

Hurricane proof houses• Stilts: Waves along coastal areas can literally

destroy a building. Buildings should preferably be built on high ground in order to avoid waves. If waves can reach the building site, the building ought to be elevated on steel, concrete, or wooden pilings or anchored to solid rock.

• Wood: Wood has a relatively high degree of flexibility which can be beneficial under certain building stresses.

Why does Galveston need protection?

• http://www.youtube.com/watch?v=MIvq_z99L7I

• http://www.youtube.com/watch?v=mJbfGUylkR0

• http://www.youtube.com/watch?v=Eh4hWUzq6A4

Sargassum

• Sargassum acts like a sponge during daily events and hurricanes by absorbing wave energy. This protects the sand from wave erosion.

BUT….The large piles of Sargassum and the

other materials restrict access to the beach and water.

The Sargassum smells bad. Tourists complain about the presence of Sargassum.

Sargassum may cause problems by interfering the choice of nesting location for turtles.

Sites where we will collect data

Site 1: Pleasure pier 25th Street

Site 2: Fishing pier 61st Street

Site 3: Galveston State Park

How could we collect data?

Ideas about how we could collect data

• Field Sketch Even in this day and age with cameras on

our phones you need to be able to do field sketches

A field sketch is used to highlight the significant things in the field of view that you would want to annotate.

Annotated photos

Direction of waves

• Decide on an appropriate distance to measure longshore drift

over, for example, 10 metres.• Lay out tape measure close to water and mark start and finish

points.• Place your float into water in the breakwater zone at the start

point.• Observe and time the object's movement across the pre-set

distance. • Similar results can be obtained if the distance travelled by the

object is recorded over a specified time, for example 5 minutes.

Measuring the build up of beach material beside the groynes

Questionnaire…Example 1. Are you local (from Galveston), if not please state 2. Are you aware of the sea defences along the coast in Galveston. ( if no

then record that and STOP questionnaire)

Land use survey

People count