by Stephanie Gross
Sunday afternoon, I swung by the Gentilly rain garden on Wildair Dr.
Much like the Forshey site, water could be seen puddled by the dropbox, bases of trees, and in the ditch of the rain garden. Drains leading from the streets had debris and trash, but nothing too large to majorly disrupt the flow of water into the rain garden.
As mentioned before, pollutants in the form of fertilizer, motor oil, metals, grease, pet waste, etc. are filtered out by soil, roots of plants, and compost, so the garden naturally improves water quality.
Just as the Forshey site, spider lilies, palmettos, Cypress trees, and Louisiana grasses are seen growing. And in a few spots you can see irises too!
I hope you’ve enjoyed the pictures. Chemical analysis will be provided at a later time.
According to The National Weather Forecast, New Orleans will receive somewhere between 4 to 6 inches of rain fall today. Combined with the intensity of rain from yesterday, runoffs and possible flooding will affect many areas in our city. It’s good to see the beautiful rain garden in Midcity (Forshey St.) collecting water not only in the ditch but also the dropbox.
Drains that divert water from the streets into the rain garden are relatively clear with a bit of trash and debris at the edges. Before the street will flood, runoffs will enter the rain garden and the plants will filter any pollutants in the form of fertilizer, motor oil, metals, grease, pet waste, etc.
While the irises are no longer present in the ditch, spider lilies, palmettos, Cypress trees, and Louisiana grasses are seen growing. There root systems are soaking up rain water and acting as organic filters to remove high nitrogen, phosphorus, iron, and metals from the soil. Compost at the base of these plants also helps with filtration.
As for the water chemistry, a few tests have been completed but more processing needs to be done before I can report the findings here. Hardness tests are in the range of 80ppm both inside and outside the dropbox.
Try to keep dry, but know that these natural environments are doing their part to offset the affects of flooding.
by Stephanie Gross
A great amount of rain hit New Orleans last weekend and we’ll see more this weekend as well.
Again the Forshey site did not collect any water in the dropbox or ditches, so no water chemistry was performed. I believe this site is not effective at collecting water. Water was collected from the the Wildair site. Here are the water chemistry results:
by Stephanie Gross
What is a rain garden?
A rain garden is a garden that collects storm water, filters out chemicals, and reduces flooding.
You can think of a rain garden as a buffer zone. Instead of dumping storm water into the drainage system or in our bayous and rivers, runoffs from storms are collected in a rain garden and are filtered by native plants to remove chemicals. A well constructed rain garden is often depressed or bowl shaped to encourage water accumulation into the garden. It should have soil that absorbs water and drains within a few hours. Soil that keeps pockets of standing water would be undesirable because it facilitates mosquito breeding.
Many harmful chemicals such a pesticides, fertilizer, motor oil, metals, grease, pet waste, etc., collected in runoffs find their way back to water treatment centers where they must be removed from the water supply. Rain gardens organic construction acts as a filter. Soil, plant roots, mulch, and even fungi and bacteria break down these harmful chemicals naturally.
Planting water loving plants like Cypress trees, Louisiana irises, Spider lilies, and native grasses – all which can be seen at the Wildair and Forshey sites- not only beautifies the area, but also encourages these native plants to do what they do best- minimize water accumulation and reduce erosion.
These key features of a rain garden are very important in New Orleans neighborhoods. Enjoy these rain gardens for their beauty and for what they provide you by reducing flood water. If you see trash or debris obstructing the drainage or harming the plant life, please remove it and dispose of it properly. This is an ongoing project to solve water problems that our city faces.
by Stephanie Gross
This is a follow-up to the water chemistry post I made earlier this month. I have been monitoring a garden on Forshey St in Hollygrove and another on Wildair Dr in Midcity since April 2015, just about six months. The two sites have bowl shapes or deep ditches surrounded by native plants and grasses such as Taxodium distichum or cypress trees, Muhlenbergia capillaries which are known as Poas or grasses, Sabel minor also referred to as a palm or palmetto, Hymenocallis liriosme or spider lilies, and several Louisiana irises.
Above: The Forshey rain garden with cypress trees lining the garden, lilies and irises in the flower beds, and grasses behind the flower beds.
Above: Wildair rain garden with grasses seen towards the front left, irises in the water, spider lilies can be seen in the flower bed which also have grasses, and small cypresses are lining the exterior of the property.
I believe the gardens are functioning well, collecting water from rainfall and run-offs from the street. They are not only prevent flooding from large rain events, but also are filtering undesirable chemicals. Water chemistry data shows that low levels of phosphorus, nitrogen, and metals are detected with regular water sample collection. Additionally, I have never found standing water at either site 24 hours after a rain event, which is important for reducing mosquito activity.
There are a few undesirable issues, however. During an intense rain even in May, two cypress trees were damaged at the Wildair site.
Above left: A cypress had to be pruned because high winds snapped the bark in two. Above right: A stake had to be attached to another cypress so that it would grow upright.
The cypresses are now looking healthier.
Above left: The pruned cypress in June. Above right: Both the pruned cypress and the staked cypress look healthy in August.
In terms of water collection, water was collected from the Wildair site at least once a month and only once in the past six months at the Forshey site. The Forshey site is not as bowled or depressed as the Wildair site, which may be affecting its functionality. Sure, one part of the city may have more rain than the other, but I do not believe that frequency of rain alone is affecting this difference in these two sites.
My observations are being shared with Water Works, Bayou Land RC&D, and the Mosquito & Termite Control and of course on this site. Data collection and progress reports are still being generated for continued study of these sites.
*click on images to make them larger*
by Stephanie Gross
STEM is an important academic discipline that is a hot topic in the 21st century. It is an acronym that includes the fields of science, technology, engineering, and mathematics. So, it’s always great news to hear that some of the best of the best are being educated right here in New Orleans. Community Liaison Jada Woods has been monitoring one of our rain gardens and here’s a little background about her:
“My name is Jada Woods and I am a recent graduate of Sci Academy. I am currently attending Bard College on a Posse scholarship, where I intend to major in environmental science. Choosing my major was very tough, but I realized that I wanted to major in environmental science right after I started working with Water Works, Bayou Land RC&D, and the Mosquito & Termite Control board. The goal of the water quality monitoring project is to make sure the water is safe and healthy for the ecosystems and human contact by treating the polluted rain runoff. The lot that I am in charge of will help cut down flooding in New Orleans neighborhoods after heavy rain. Collecting water right after it rains gives me a chance to see the process of the bioretention cell. Working with Water Works, Bayou Land RC&D, and the Mosquito & Termite Control board has given me an insight on what it means to care about the environment.”
Well done, Jada. It’s sad to see you go, but we wish you continued success in your studies.
by Stephanie Gross
It has been a wet week- perfect for reporting the data collected at the Forshey and Wildair sites.
As Zachary mentioned previously, there is a difference between Forshey and Wildair rain gardens. I attempted to make two water collections this week to test water chemistry at Forshey. My first attempt was Monday after 5:00pm – but the dropbox was dry. I checked the dropbox again on Friday after 5:00pm and only a few milliliters of water was present- not enough for water chemistry test. Hardly what I expected to find.
Wildair, however, had enough water collected to collect and analyze. Here are the results on the water chemistry:
Over time and with more collections, we will be able to analyze this data to determine what parameters change with both seasonal and environmental changes. Trends will be noticed, hypotheses will be tested, stats will be calculated- oh my!
Coming soon, I’ll describe the habitat and show you plenty of pretty pictures!
NOLA Rain Gardens Monitoring
by Zachary Batterman
I have been monitoring and observing two rain garden sites in New Orleans since December 2014. One site is located at 8641 Forshey St in Hollygrove, the other is located at 5301 Wildair Dr in Filmore. The first thing I noticed about these two sites is that although they are only located several miles away from each other, they both respond differently during rain events. I have observed that the Wildair rain garden generally accumulates more water during and after a rain event. This could be because the site receives more rain during events or has poor drainage compared to the Forshey site. I have been able to collect a water sample from the retention cell at Wildair up to 48 hours after a large rain event, whereas the Forshey site will be dry after the same amount of time. I believe this must be associated with the amount of rain each site receives because other factors such as erosion, vegetation coverage, condition of plants and the amount of unwanted vegetation have been very similar at each site over time.
As far as analyzing the water quality indicators, both sites have had very similar results. I have been testing dissolved oxygen (DO), temperature, nitrate-nitrogen, phosphorus, bacteria (fecal coliform), chlorine, copper, hardness, iron, and Ph. Both sites have tested consistently similar for the following; DO: 4-8ppm. Temperature: Varies per visit but has not seemed to impact other indicators significantly. Nitrate-nitrogen: 0-5ppm. Phosphorus: 1ppm. Bacteria (Fecal Coliform): Positive. Chlorine: 0ppm. Hardness: 40-120. Iron: 0ppm. Ph: 7 or 8. While these sites are located several miles apart, they are both located in residential neighborhoods and most likely have the same inputs of chemicals and bacteria, resulting in similar water quality results.
The rain garden project is working in partner with the Mosquito&Termite control board to monitor if these sites are creating ideal breeding grounds for termites and mosquito’s. Since I have been monitoring these sites from December through April I have not seen much activity because we have been in the winter months. However, in my most recent monitoring I have noticed an increase in insect activity. My only concern here would be the standing water (specifically at the Wildair site) after rain events. Standing water is a prime environmental condition for mosquito breeding. However the standing period may not be long enough to produce good conditions for breeding. From my observations so far I have been impressed with the rain gardens here in New Orleans. I think they are proving to be a good way to relieve drainage problems in the area and are given us valuable information into what the quality of the drainage water is in these neighborhoods.
Hopefully through the combined effort of Water Works, Bayou Land RC&D, and the Mosquito&Termite Control board we can continue to monitor these gardens long into the future and provide valuable data to help improve the communities we live in.