Manipulating Seawall Texture to Enhance Biodiversity in Abu Dhabi Marinas

Student: Gabrielle Branche
Supervisor: John Burt

Many cities around the world are experiencing increased urbanization and human population growth. This ultimately comes with challenges both inland and at sea, particularly pertaining to environmental protection. Roughly 70% of the world’s largest cities are situated along coasts which results in the replacement of natural shorelines by artificial ones. In fact, coastal infrastructure occupies more than half of the shorelines in cities bringing additional pressures on marine biodiversity offshore.

The Arabian Gulf is no stranger to coastal infrastructure as it is a rapidly growing region. The Gulf is known to have > 40% of its coastlines classified as heavily modifies as early as the 1990s. This trend has significantly increased with developments such as Dubai’s Palm Islands or Doha’s Pearl. With little indication of urbanization slowing down in this region, it is crucial to find ways to preserve the natural ecology of the marine ecosystems in the gulf.

Seawalls and breakwaters are some of the most commonly used structures to safeguard cities from floods and storms. Seawalls are vertical stone structures that redirect waves back into the sea ensuring that rising sea levels have a minimized effect on the coast. In the present day, seawalls are mainly built using precast concrete units which are easy to modify and scale. The malleability of precast concrete provides opportunities to determine the ways in which the infrastructure may positively impact marine fauna inhabiting the coastal area.

The goal of this research project is to use eco-engineering to determine how the landscape of a seawall can inform the biodiversity of seawalls in Abu Dhabi. By inserting 22cm x 22cm tiles into seawalls in 3 different marinas in Abu Dhabi, it can be observed how varying groove size on seawalls can allow for more biodiversity to grow and develop on the material. For this project, tiles were manufactured with 5 groove sizes ranging from 0.5mm to 1cm as well as a mixed tile and a control smooth tile. They will be inserted at the intertidal zones of the marinas and monitored over a six-month period.

As part of this Post-Graduate Practical Training Program (PPTP), we will be inserting, observing, and assessing the accumulation of organisms on the tiles using a Nikon D700 SLR camera contained within a waterproof Ikelite housing. Within the next couple of weeks, we will insert the tiles using underwater drills to fix them to the seawalls at the three marinas. Then, within the next two months, there will be biweekly visits to the three marinas to collect data on the tiles and monitor how the biodiversity is developing. Based on the result of the project, we can begin to find optimal concrete cast designs for future coastal development projects.

This project is not only beneficial to the research team but also can bring public attention to the efforts of the marinas to provide sustainable solutions to challenges brought about by urbanization. As such, an additional task that may be completed through PPTP is developing a social media presence for the project and the marinas being used to complete them. This aspect of the project is still being fleshed out but may be used to bring awareness to the need for coastal protection and what is currently being done for it to the general public.

The work of PPTP would contribute to Phase 2 of a 3 part initiative in which design and development (phase 1), deployment (phase 2), and analysis (phase 3) are all executed.