Brookhaven, GA – Brookhaven resident, William Van Landingham, offers readers a perspective in the following Letter to the Editor, “How to win the storm water war (that we are currently losing).”
Part 1: The storm water problem
We are in a house by house battle with thoughtless residential developers to halt the increasing storm water flooding we are experiencing on an alarming scale. Every time an old house is demolished and the natural vegetation stripped from the lot, storm water velocity and volume increase dramatically especially during a heavy rain, often resulting in flooding the downhill neighbors.
This new flooding caused by construction is due to the dramatic change in the impervious surfaces that rainwater absorbs into such as grass, bushes, roofs and driveways. Surfaces like a roof or a concrete driveway will drain rainwater rapidly and are very impervious creating a surge of storm water (increased volume and velocity) during a heavy rain. Conversely, a heavily vegetated yard or garden will absorb the rainfall into the spongy soil and root system stored to be used later by the trees and plants. Eventually it will be absorbed by the plants and then evaporated, making it a very pervious surface and a natural rainwater store.
Also if the natural contour of the land collects and retains storm water in swales, terraces or rainwater gardens, additional storm water is prevented from becoming floodwater. Allowing rainwater runoff from a heavy rain to be slowed down, stored and absorbed means less flooding downstream. It also reduces irrigation needs and conserves water.
This is not only a critical issue for those who live directly on a stream or tributary, but for any property owner that has a ditch or gully in their yard that channels storm water from uphill neighbors. Periodic flooding to a home will create health issues for the occupants due to mold and mildew, foundation settling damage and soil erosion. Periodic flooding will raise the underground water table in low lying areas or areas where water naturally collects making basements that were previously dry now wet or flooded during heavy rains. A home for sale that floods periodically must be disclosed by a real estate agent to any potential buyer so the market value drops to only the value of the lot, with the house now a liability in need of demolition.
As a community we need to ask ourselves these important questions:
- Should a residential building permit be required to address storm water management and flood control issues that the construction may cause?
- Why are most new residential construction or re-development permits issued without requiring a storm water flood review?
Part 2: The Loophole for Residential Developers
Our local building codes and officials successfully regulate plumbing, electric, structural design and many other construction topics and are critical to having houses built that meet health and safety standards. The Georgia Storm Water Management Manual, which is mandated by state law and is enforced by our local building authorities requires a builder to develop a storm water management plan to consider these issues before construction begins. But there is a very big loophole for residential developers. This loophole essentially allows almost any new residential construction or re-development to be exempt from filing a storm water management plan, thus avoiding apparent responsibility or having to acknowledge the potential consequences of their actions. And when a local building department issues the construction permit without requiring consideration of storm water and flooding issues, they have effectively agreed no plan is required (or needed) even though a site visit to the property prior to allowing construction would easily reveal potential flooding is possible or likely. This is the wrong approach and needs to change. This approach allows the storm water laws and regulations that protect our community to be circumvented. This approach shifts the economic liability and responsibility from reckless developers to downhill property owners and also to tax payers who must repair and maintain roads, bridges and storm sewers damaged by floodwaters.
The Manual Vol. 2 section 184.108.40.206 allows an exemption for residential developers if they don’t increase the impervious surfaces by more than 5,000 additional square feet, or don’t clear more than 1 acre of land. The Manual does not define what an impervious surface is or what surfaces (roof, drives, etc.) should be included in this calculation by local building authorities. But many local building departments use a quick rule of thumb and add up the existing roof (footprint) and driveway square footage then compare it to the proposed roof and driveway square footage, and if the increase is less than 5,000 square feet, the permit is issued without requiring a storm water plan and thus, no minimum requirements need to be met or reviewed by the building department officials.
Counting just roof and driveways as the only impervious surface to be used in the calculation is the source of the loophole and a misapplication of the regulations. This method is arbitrary, inaccurate, and has resulted historically in allowing construction that has produced harmful floods during construction and continued flooding after construction is complete. Considering the amount of houses currently being demolished and developed, the harmful effects to our neighborhoods are cumulative and irreversible. If allowed to continue, low lying properties will face increased flooding frequency, intensity and water depth with devastating long term consequences.
The loophole works like this: An older house of 1,500 square feet with a 500 square foot driveway on a 15,000 square foot (+1/3 acre) lot can use the loophole to increase the proposed house and driveway area to 7,000 square feet (1,500 + 500 + 5,000) and claim the exemption when applying for a demolition and building permit. However when demolition begins, excavators and bulldozers with metal tracks strip any vegetation down to clay, and rough grade the lot for drainage (still less than the 1 acre that would trigger the requirement). They might dig a basement and pile up any excess dirt and cover it with plastic. They might remove trees and stumps or bring in fill dirt. In any event, up to 15,000 square feet of land can be disturbed and stripped of all vegetation and the compacted clay now sloped for drainage so their site will not flood. The entire 15,000 square foot lot is now very impervious compacted clay and will drain rainwater almost as fast as a roof or a driveway, with an enormous increase in the volume and velocity of storm water rushing downhill now that almost no rainwater is absorbed since the vegetation is gone. It will now erode and any failure of silt fencing will allow the transport of silt and pollution directly to our rivers and streams. Downhill neighbors will realize a violent rush of storm water after a heavy rainfall and will backup and flood. As the flood water eventually drains erosion usually occurs.
We know that thick grass, plants and trees with deep soil and established root systems will absorb much more rainfall than the same area stripped of trees and vegetation and the underlying clay soil compacted by construction equipment. Installed silt fence is usually mandatory prior to construction but is designed and useful to trap silt and debris, but not water. Just take a drive during and right after a heavy rainfall and observe local construction sites to see the immediate effects. Local flooding can occur in minutes as storm water discharges increase dramatically and overwhelm existing storm sewers. Rapidly moving floodwater is dangerous to property and human life and causes damage to bridges and other structures.
After the house is completed, the lot is often graded to directly slope downhill with roof gutters and driveways discharging for maximum rainwater runoff, with a layer of sod laid directly on the compacted clay. Apparently most developers intuitively understand they must protect THEIR house from flooding, while selfishly placing neighbors in flooding peril, so they slope the land and arrange the downspouts so they don’t flood without regard for the adjacent property owners.
While the Manual does not define what is an impervious surface (such as roofs and concrete driveways) it does define impervious rates for various types of surfaces. Much of the Manual is dedicated to the methods used by civil engineers and hydrologist when they design a storm water management plan. These plans often involve retention structures, underground drainage pipes, inlets, wetland areas, ditches, swales or other methods to slow down and store the water to be absorbed or released slowly downstream.
The Manual gives authority to local building officials to enforce its provisions. As a public safety issue and a public infrastructure issue, it is not unreasonable to expect a careful and thoughtful storm water assessment be discussed and a plan that is designed to prevent flooding and environmental damage be in place before a residential building permit be issued.
Part 3: Solutions
There needs to be a balance between allowing future development and protection of existing homeowners while we always insure the environment is protected.
Require residential storm water plans be submitted and approved prior to construction
The Manual deals with the planning, designing, calculating and building adequate storm water controls so floods and erosion do not occur and our environment is protected. The current rule of thumb method used by most building departments allows developers to evade the intent of the law. Local government needs to pass ordinances requiring residential building permits to include a storm water management and control plan requiring the builder to demonstrate they have taken all the necessary and reasonable steps to adequately prevent flooding or downstream damage. This will require them to think about the consequences of their actions and consult their planners and engineers to protect the adjacent property owners, community, environment and rivers during and after construction.
Work together for common solutions and best practices
Good storm water management does not have to be expensive nor be dominated by unsightly concrete structures. The best residential planners and designers routinely incorporate storm water principles and practices into their site plan (best practices), and build in an environmentally responsible manner. Building officials would have less problems involving homeowner disputes arising due to construction flooding. Our creeks, streams and rivers would be cleaner with less habitat damage and erosion. Our existing public storm water system will not become overloaded and need expensive repairs or upgrades. Bridges, roads, parks and greenways will not face erosion threats. There are many benefits to controlling storm water during construction, and very little additional cost required of a residential developer.
Use lawsuits to recover flood damages
For those developers who care so little about damaging the downhill neighbor’s property and build selfishly in an insensitive manner, a homeowner may have no alternative but file a lawsuit against the developer. Consider that a builder and the subcontractors normally have liability insurance that can pay monetary damages due to their actions. Also consider that the nuisance laws of the State of Georgia allow the recovery of damages from flooding, and can also place legal responsibility on individuals that cause flood damages to be held personally liable. An unsuspecting home buyer can inherit the legal liability for flood damages from a developer that created the nuisance, and be liable for continuing damages until the cause of the floodwaters is corrected. Real estate brokers can be held liable if they knew or should have reasonably known of flooding issues and fail to disclose those facts to a buyer.
If your home and neighborhood is worth saving and you feel threatened by flooding from uphill construction, then seeking legal counsel for advice to determine if a lawsuit may be your best solution.