Grantee Research Project Results
Making Extreme-event-stable Shorelines with Hyacinth (MESH)
EPA Grant Number: SU840400Title: Making Extreme-event-stable Shorelines with Hyacinth (MESH)
Investigators: Hustvedt, Gwendolyn
Current Investigators: Hustvedt, Gwendolyn , Cade, Tina , Mettenbrink, Eliot , Kenchanna, Dhanush , Brooks, Nicole , Delong, Daniela , Mendoza, Jennifer , Fogelsong, Grace , Galan, Mya
Institution: Texas State University
EPA Project Officer: Spatz, Kyle
Phase: I
Project Period: July 1, 2022 through June 30, 2023
Project Amount: $25,000
RFA: 18th Annual P3 Awards: A National Student Design Competition Focusing on People, Prosperity and the Planet (2021) RFA Text | Recipients Lists
Research Category: P3 Awards , Sustainable and Healthy Communities
Objective:
The objectives of the study are to design a low-tech, community-based material that will prevent shoreline erosion especially during extreme weather events, absorb hydrocarbon polluted water, support germination of seeds of dune stabilizing plant species and produce a fertile soil amendment after composting. An additional objective of the project is to reduce environmental, economic and health threats caused by an invasive species in coastal waterways through the removal of water hyacinth.
Approach:
The research procedure will involve three main phases of activity: designing and producing the cord material and mesh technology, testing the ability of the mesh to meet the four objectives of the project and determining the best formulation for composting the mesh after testing. The procedure embodies the P3 approach of cradle-to-cradle design by taking waste and making it into a socially, economically and environmentally supportive solution.
Members of the P3 design team will create the mesh prototypes by cleaning and softening the stems of water hyacinth plants collected in the San Marcos River in a solution made from household chemicals and then drying them in the sun and/or an oven. Stems will then be flattened and twisted by hand into cords and netted into mesh using traditional netmaking methods.
An artificial shoreline will be created using a shallow pool filled with rocks and sand to mimic the composition of shorelines in South Texas. The artificial shoreline will be secured with the mesh material similar to anchoring a sand dune in an actual beach environment. Extreme weather event conditions will be recreated by sharply angling the test pool and manually shaking it. Additionally, wave and surge conditions will be created using hoses and sprayed water. Beach material that escapes from the pool during testing will be measured.
The mesh will be tested for its ability to absorb and hold polluted water by soaking it in a “broth” containing petroleum hydrocarbons such as motor oil, gasoline or antifreeze. The pollution control performance will be quantified with both kinetic and isotherm experiments to obtain the rate and extent of contaminant removal. Both Total Petroleum Hydrocarbons and Chemical Oxygen Demand will be measured before and after the testing. The soaked mesh will be transferred to a prepared compost pile, and the remaining broth in the pool will be taken to the University’s Environmental Health Services for appropriate disposal.
At least three smaller mesh will be netted from cord that has an additional strand of cellulose pulp (which can be produced from hyacinth plants) and has been embedded with a mix of seeds for plants that are indigenous or well-adapted to South Texas shorelines. This mesh will be placed onto simulated beach dunes in a mesocosm equipped with water sprayers mimicking local rainfall intensity. Simulated dunes and mesh will be monitored to evaluate the revegetation of areas using the mesh using a “greenness rating” of vegetative coverage.
Expected Results:
The MESH project creates a holistic solution to multiple issues that occur in waterways: proliferation of invasive species, shoreline erosion, and water pollution. The results of the MESH project will be an inherently benign, low-technology material that uses integrated textile, engineering and horticultural knowledge to help small, rural, tribal and/or disadvantaged communities reduce the impact of extreme events such as hurricanes or flooding on the fragile shorelines. The outcomes of the project include a) methodology to produce hyacinth-based cords and mesh and evidence of the mesh’s ability to b) reduce shoreline erosion, c) absorb hydrocarbon polluted water, d) support germination of dune stabilizing plants, and e) be composted following deployment in polluted water. By integrating technology and processes drawn from several applied fields, MESH will produce educational outcomes and documentation of methods that can be adopted by small, rural and/or indigenous communities that seek to address the impact of extreme events on their local economy and environment.
Publications and Presentations:
Publications have been submitted on this project: View all 1 publications for this projectSupplemental Keywords:
Beach Dune Management, Compost, Environmentally Benign Substitute, Invasive Species Management, Recycled Materials, Waste to ValueProgress and Final Reports:
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.