May 20, 2008
Dear Arroyo Colorado Watershed Partners,
First of all, the meeting summary notes from the April 15 Outreach and Education Workgroup Meeting and the April 24 Steering Committee and Habitat Workgroup meetings are available and posted on the website.
Again, the field trip to the Invista (formally Dupont) constructed wetland site in Victoria, Texas is scheduled for Thursday, June 12, 2008. Please let me know if you are interested in attending this all day event. Priority will be given to Habitat and Wastewater Infrastructure Workgroup members. See the attached pictures for a preview of the water treatment wetland and the outdoor classroom. Additional information will be sent to interested individuals and workgroup members.
Last week I attended the "Constructed Wetlands Today" conference and came back with some insight in regards to creating and maintaining wetlands. The first thing driven home was the multiple layers of value inherent in the development of wetlands. Many already know the value of wetlands for wastewater treatment, habitat, education, and passive recreation, but other values include carbon sequestration, increased property values, and public relations/community marketing. The bottom line is cumulative community benefits from the overlay of wetland uses and functions.
Constructed wetlands are dynamic robust systems and attention must be paid to every aspect of planning, design, operation and maintenance. There is a lot to wetlands systems and the following are just a few excerpts from my conference notes in regards to lessons learned.
- It takes a team to plan and design a treatment wetland. Important to involve an engineer, biologist, and the operator. Most success when operators were involved from the start.
- Operating a constructed wetland is like farming; the operator must be a good observer and sensitive to seasonal changes.
- In the design phase, one must consider hydraulic retention time, minimum area needed to meet treatment objectives, and test design equations against site constraints.
- Sedimentation zones, multiple cells and treatment trains are important to allow for maintenance and/or upsets in a system. Equally important is the ability to control water levels and maintain even flow (sheet flow) through the wetlands. Open water zones helps balance the system and control invasive plants and maintain diversity.
- The life of a constructed wetland (treatment effectiveness) is 25 to 50 years before rejuvenation is needed. At some point, it will be necessary to remove some vegetation, re-grade and replant.
On a final note, our local grant writer Amy Rangel, has been accepted into UTPA Physician's Assistant Program and will be leaving her position as Program Assistant for the Arroyo Colorado effective June 30. Amy has done a fine job for us and she will be missed. The position is posted and we are looking for applicants and would appreciate your help. If you are interested or know of someone interested, please pass the word along. To view the posting, go to greatjobs.tamu.edu, Notice of Vacancy Number: 03430, Position Title: Program Assistant for the hiring unit: Texas Water Resource Institute.
Have a great day, Laura