Hurricane Harvey // Sand Peel Sculpture X

Context, Description, and Interpretation:

Peel X records erosion during the maximum flood and deposition of sands during the middle adjustment phase as the energy levels drop.  The hydrologic archive shows the peak flood followed by water level dropping at a decreasing rate.  During this time the human impact recorded by 211 calls was dominated by immediate needs like food and shelter.  At this location 2019 Hurricane Imelda deposits are stacked on 2017 Hurricane Harvey deposits which are stacked on 2015 Memorial Day flood deposits, illustrating the need for resilient mitigation plans.

Summary: Peel X shows an overall increase in energy and velocity upwards.  Below the Hurricane Harvey erosional surface (red line), contorted beds, organics and roots indicate a previous deposit that has been modified by plants.

The lower half of Peel X is full of organic material including some plant roots that are oriented vertically.  These roots indicate deposition prior to Hurricane Harvey after a previous storm event.  Wavy laminations throughout this organic rich package of sediment are interpreted to be the remnants of depositional features modified by plant roots and animals. The maximum flood erosional surface is near the middle of the peel (red line), overlain by large scale trough cross stratified sediment deposited as dunes.  Organic material is deposited in the troughs.  The red arrows indicate the easterly flow direction.

Event timing

• Pre-Harvey phase, Memorial Day flood

  • May 27-30, 2015: Buffalo Bayou reached a water level of 10.3 m (33.8 ft) on May 26, 2015 which marks the biggest storm event just before Hurricane Harvey. It is likely that the lower half of the peel was deposited due to this storm event, then reworked prior to Harvey.

• Flood phase

  • August 28, 2019: The red line marks the Hurricane Harvey erosional surface.  This erosion occurred during the flood phase as Buffalo Bayou rose to its peak at about 1:00am on August 28, with a measured gauge height of 15 m (41.9 ft).  Flow was to the east.

• Middle adjustment phase

  • August 31-September 5, 2017:Dunes were likely deposited during this time of lower flow regime. The lack of a high energy early adjustment phase may result from the position of Peel X on the downstream end of the sand body. Flow was to the east.