Hall & Hall BLOG
TOPSOIL TO THE RESCUE
Across Eastern Iowa, communities from North Liberty, Coralville, and Cedar Rapids are implementing new ordinances related to post-construction topsoil restoration.These new laws are a response to the 2015 Iowa Department of Natural Resources ruling that required developers and/or homebuilders to restore topsoil at the completion of construction.
The ruling did not become state law, and is now being considered at the municipal level of government.
On Tuesday, December 6, 2016, the 2nd largest city in Iowa, Cedar Rapids, passed their version of ordinances, (71 & 72), requiring a stricter topsoil standard for future developments. The hope is to enhance water quality, reduce flooding and erosion, recharge the aquifer and provide a healthier growing medium for lawns. The new ruling requires a 4” zone of restoration to a lot post-construction.
Our view: Although there is more research needed to determine the total benefits in flooding reduction, we do feel the benefits of a healthier planting medium for seeding or sod to grow in will result in healthier lawns requiring less toxic fertilizers and herbicides, as well as much less watering demands and reduced maintenance.This leads to reduced lifecycle costs for homeowners.In the long-term, the reduction of harmful toxins will mean less toxic runoff, thereby improving the quality of water and the environment, and improving the health of everyone, reducing healthcare costs in the future.In the end all will benefit!
LOVE IN THE TIME OF RAIN GARDENS
Have you ever heard of a rain garden?
The following is an introduction to this widely-used best-management practice.
What is a rain garden?
A rain garden is a depressed area filled with plants that is designed to collect stormwater that flows off impervious surfaces and hold it until the water can be absorbed by the ground. Impervious surfaces might include driveways or parking lots, roofs, and greenspace with soil too compact to allow water to percolate into the soil.
The vegetation selected for rain gardens is recommended to be species that are native to the region. The native species, already adapted for the local climate, soil and water conditions, are more likely to thrive and grow than non-natives. Drought-resistant native vegetation, called succulents, are commonly used in a rain garden because they do not require any additional water than the stormwater it collects.
Stormwater naturally picks up fertilizers, oils, trash, and other contaminants in its journey across impervious surfaces leading to storm sewer drains. However, rain gardens can serve as barriers that prevent the contaminants from flowing directly into storm sewer drains, and into our water supply. When diverted to a rain garden, stormwater and its contaminants are instead isolated there and allowed to percolate down through the soil profile while being naturally filtered and cleansed prior to entering the water supply.
How is a rain garden different from a detention pond or a bioswale?
The biggest difference is that rain gardens are not primarily designed to manage stormwater. A detention pond is designed to collect and gradually drain stormwater and bio swales are for clearing silt and debris from stormwater, on its overland journey to a storm drain. Rain gardens, on the other hand, are actually designed to allow rainwater to infiltrate directly back into the soil profile instead of running through a city’s storm sewer system to the river, and ultimately an ocean. The key to remember is that rain gardens remove the storm sewer drain component from the stormwater management process.
What are the benefits of a rain garden?
- They’re attractive! Rain gardens actually have the potential to raise land values or improve the marketability of property. Much like traditional landscaping, a rain garden adds a nice visual aesthetic. But, unlike most traditional landscaping, rain gardens provide an additional tool to manage stormwater and commonly require little to no watering once established.
- Rain gardens help offset the effects of urbanization. Natural drainage patterns have depressions that collect stormwater and perform the exact function of a rain garden, but when land is paved over and built upon, these natural depressions are eliminated, and stormwater flows over the new impervious surfaces at higher than natural velocities.The higher flow velocity can create ruts, outwashes and create erosion which can reduce the amount beneficial organics and topsoil, and increase the amount of contaminants in the water.This will, in turn affect water quality for municipalities.
- Rain gardens are flexible in their size and functionality. They can be large enough to handle an entire big-lot store parking lot or small enough to take the rainwater from your residential home gutters.
What about creating places for mosquitos?
This is a common concern and no one wants to provide additional breeding grounds for a disease-carrying pest, like mosquitos. However, with proper design, the rain water collected doesn’t stay around long enough for mosquito larvae to hatch.
Creating a Rain Garden
For home and small business owners who are willing to get their hands dirty, it is possible to create to your own rain garden with minimal effort and cost. There are plenty of online resources to guide you through the process.
Homes, developments, or businesses that are larger will likely need to contact a local engineering firm to have a rain garden designed to meet their needs. Several items one may want to consider in designing rain gardens include calculating their size, capacity, location, soil conditions as well as suitable plants and compliance with city or regional requirements.
It is not difficult to see how one would benefit from a rain garden; helping to reduce the negative impacts of urbanization, improving water and soil quality, and increasing property values.
Firelake Event Center
Hall & Hall Engineers Inc. vast experience and talent in land development led to the design for an event center campus, public street, utility extensions, and stormwater management for a public/private development in Ely, Iowa.
In addition to Event Center, the development will include large estate residential lots that overlook a stunning lake.
The new Firelake Event Center at the summit of the site’s peak, captures unparalleled views of the golden sunsets, the starry skies, and the verdant landscape of eastern Iowa.
Driving a car is a Point A to Point B proposition. Once you get behind the wheel, you’re focused on your destination: how long it will take to get there, the route you’re planning to take, and whether or not you’ll be on time. That’s quite a different proposition from traveling on foot. Traveling a step at a time puts you in very real contact with your surroundings, every step of the way.
That’s the primary reason that urban planners are paying more attention to pedestrian traffic these days. Walking involves constant engagement with your surroundings and tends to produce greater involvement with street level opportunities. In some ways, it’s a return to the way cities were in the early twentieth century: a development that is gaining wide acceptance and approval as a new wave of urban dwellers returns to the central city.