Atlanta commercial property owners who need a new roof are already paying monthly stormwater utility bills, and for some buildings, these fees add as much as thousands of dollars every year. The Department of Watershed Management does have credits that can lower these fees by quite a bit. The problem is that you have to apply at just the right time during your roof replacement project, or you won't qualify at all.
The credit program gets tricky as you start trying to work out what qualifies. Back in 2013, Atlanta passed an ordinance that says you have to manage the first 1 inch of rainwater with green infrastructure. They've permitted almost 5,200 projects since that ordinance was finalized, and these projects have kept more than 1.1 billion gallons of water out of the city's sewer system. Your new roof project could also be part of that number! The difference between a system that only earns you a 20% credit versus one that gets you half off your bill depends on the technical specifications that most roofing contractors don't even know are out there, let alone include in their standard packages.
A few different roof technologies qualify for these credits. You just need to learn what Atlanta specifically needs.
Let's talk about how your new roof could help cut down those stormwater fees!
Atlanta property owners all pay a stormwater fee, and the amount you owe is based on how much rainwater flows off your property when it storms. The calculation is actually pretty simple when you know what the city is looking for. They measure every surface on your property where water can't soak through, and they use that total area to set your fee. Any hard surface counts toward this total - from concrete and asphalt to your roof. Your roof is usually the biggest contributor to that number.
The city has a pretty smart program in place for property owners who want to save money. They'll give you credits on your stormwater bill if you install systems that manage the water that runs off your property. Property owners can save anywhere from 10% to 40% on their monthly bills. The amount of savings just comes from what type of stormwater management systems you put in and how well they hold back water from the city's drainage system.
Commercial properties get access to a lot more credit options than residential properties do. It's actually a sensible idea by the city. A massive warehouse or shopping center creates exponentially more runoff than a typical house does, so the city wants those bigger properties to put money into large-scale stormwater management. The effect from just one commercial property can be huge.
Our sewer system just isn't built for the amount of water that we get during heavy rainstorms. Those summer storms are the worst because they can dump a few inches of rain in under 2 hours. All that water has to go somewhere, and when the sewers can't take it, raw wastewater ends up in our creeks and rivers. It's bad news for the environment and for anyone who lives downstream from us.
The federal government had to step in and make Atlanta fix this problem with what's called a consent order. The city signed it after it got hit with pretty hefty penalties for all its water pollution violations. It's a legally binding agreement that means Atlanta has to spend billions of dollars on sewer system upgrades and overflow reduction over the next few years. The stormwater credit program is the city's way to share some of that responsibility with property owners and throws in a financial incentive to sweeten the deal. Property owners who participate can lower their fees and help to make the region's waterways cleaner at the same time.
Green roofs can earn you two different levels of stormwater credits in Atlanta, and the amount you get depends on the type you choose. The standard type qualifies for a 40% credit, and the intensive version bumps that up to 50%. Either way, your roof has to hold between 1 and 2 inches of rainfall if you want to qualify for the program at all.
The main difference between these two green roof types depends on how much soil depth you have and which plants can survive up there. Standard roofs need just 2 to 6 inches of soil, and they work best with especially tough plants like sedums. These particular plants can handle Atlanta's brutal summer heat and those winter freezes that show up every year, and they take care of themselves once they settle in. Intensive roofs are different, though, because they need at least 6 inches of soil. That extra depth lets you grow many more types of plants and opens up more design possibilities for your rooftop.
Weight is a big consideration because your roof structure has to support all that extra load. A standard green roof system puts somewhere between 15 and 35 pounds per square foot when the soil is saturated with water. Your structural engineer needs to review your building before you start any installation plans.
The city made the process easier for older buildings when it approved modular systems back in 2023. These prefabricated units connect together almost like building blocks, and they make the entire installation process easier and cut down on labor time, too.
The price tag might also make you pause for a minute. You'll probably have to spend a decent amount per square foot for a quality green roof system, and that's just for the initial installation. The silver lining is that you'll start saving money on energy bills pretty quickly. Building owners usually see their investment pay off once they add up the stormwater credits and factor in those lower cooling costs throughout the year.
Maintenance is essential if you want to hold onto those credits. The city can and will revoke your stormwater credits if you neglect your green roof and let the vegetation die off or become overgrown.
Blue roofs take a different strategy than green roofs, and they can still help you qualify for stormwater credits in Atlanta. A blue roof is a flat roof that's been engineered to temporarily hold rainwater after storms. The water collects on the roof surface and then sits there for a day or two before it slowly drains away through the system.
The mechanism behind blue roofs is actually fairly simple. Special drain outlets control the rate at which water can leave the roof surface. These drains have weirs or similar flow-control devices that slow the drainage down to just a trickle. In some cases, the parapet walls around the roof perimeter might need modifications to create shallow ponding areas. The entire system lets the rainwater pool up on the roof and then slowly release over the next 24 to 48 hours.
Atlanta has particular calculation requirements that prove a blue roof design will work properly. The city wants to see that the roof is able to manage what engineers refer to as the 2-year, 24-hour storm event. In plain language, that's a moderate rainstorm that statistically happens about every other year. An engineer has to run all these numbers to verify that the roof meets Atlanta's detention standards.
Safety matters when the water starts pooling on a roof. Overflow scuppers are needed because heavy storms can overwhelm your drainage system completely. These scuppers work like emergency exits for all that extra water. A structural engineer also needs to check that your roof is strong enough to support the weight of standing water.
Commercial roofing membranes work well with these blue roof systems. TPO, EPDM and modified bitumen are all solid options. These materials are tough enough to handle temporary water ponding just fine. Every roofing manufacturer has their own warranty policies about intentional water detention, though, and it's worth checking those policies before you move forward with installation.
Blue roofs usually earn a 20% to 30% reduction in stormwater fees. The credit percentage is lower than what green roofs receive because blue roofs don't filter pollutants or absorb water in the same way that vegetated systems do.
Detention options might already be part of what you're thinking about for your new roof project. Cistern systems are also a great way to earn those stormwater credits, and they work quite well for most properties out there. Atlanta has a minimum requirement for credit eligibility, and it's set at 1,000 gallons of storage capacity. The math works out pretty favorably as you increase your storage past that baseline. Most property owners who connect their cisterns to their roof downspouts get a 10% to 25% reduction in their stormwater fees, and it adds up fast.
A first-flush diverter has to be there for these systems to work correctly and meet city requirements. That first runoff carries dirt and debris from your roof surface, and it needs to stay separate from the water you're actually storing. Cisterns work best when the stored water stays clean enough for irrigation purposes, and nobody wants contaminated water in their system anyway.
Tank placement needs some strategic thinking and relies on a few factors about your property. Above-ground cisterns are usually the preferred option because the installation and maintenance are simple and affordable. Below-ground tanks save valuable space, though the installation costs run much higher. Commercial districts have extra screening requirements, too. The customers and business neighbors probably don't want to see giant water tanks during their shopping trips or lunch breaks.
Mosquito prevention isn't optional with these systems, and health codes are strict about sealing requirements. Standing water turns into a breeding ground fast without the right precautions in place. An overflow pipe connection is also mandatory to handle the excess water when those heavy storms roll through Atlanta. Leave this out, and your solution will turn into a flooding problem quickly.
Cisterns integrate nicely with most existing roof designs and keep renovation costs down. The dual benefit of irrigation savings and credit reductions makes the investment worthwhile, especially when Atlanta implements those drought restrictions that seem to pop up every few years.
The paperwork for Atlanta stormwater credits is where most projects run into big problems, and you don't want to be one of them. You have to get pre-approval from the city before any construction work begins. The city is extremely strict about this requirement, and they will reject your application if you've already started. It doesn't matter if your new system is working great and prevents thousands of gallons of runoff each month.
Your application package is going to need a few main documents for the city to even look at it. The engineering plans have to be stamped, and they need to include all of the runoff calculations in detail. Atlanta also wants an operations and maintenance agreement that shows your long-term care plan for the system. Once construction is done, you'll need to submit the as-built certifications as proof that you actually built what the plans showed.
The review timeline is anywhere from 30 to 60 days in most cases. Sometimes it stretches out longer when the permit office downtown gets backed up. Most applications get rejected for one of two reasons. Either the maintenance provisions fall short of what the city needs, or the runoff calculations have errors in them. A professional engineer should certify those calculations. The formulas are deceptively hard to work with, and DIY attempts usually get bounced back.
Approval is the beginning of your responsibilities, though. March 31 is the deadline every year for your annual report that documents your maintenance activities. The city also mandates a system recertification every 5 years. Missing that annual report deadline or letting the maintenance slide means that the city can pull your credits completely. At that point, you're paying full stormwater fees all over again.
The financial consequences pile up fast when mistakes happen. You lose the credits themselves. But the city can also hit you with fines for not following your maintenance agreement.
After your documentation is all set and ready to go, the next step is to figure out just how much money you can save with these credits. Atlanta actually lets property owners stack different types of credits together, which leads to some pretty significant savings. A green roof combined with a rainwater harvesting system could knock 60% to 70% off your stormwater fees.
Real numbers help put this into perspective. A commercial building with a 50,000 square foot roof could be paying $15,000 a year in stormwater fees right now. The right combination of improvements could save that property owner somewhere between $9,000 and $10,500 annually. That money builds up fast when it compounds year after year.
The city has one important requirement, though, and trips up a lot of property owners. You can't double-dip on the benefits from multiple systems. Your green roof might capture 40% of the runoff, and your cistern system might take care of another 40%. The math would make you think that you'd get 80% credit. But because these systems overlap in what they accomplish, the city will probably only give you 60% to 70% total credit.
The sequence of your improvements actually matters quite a bit in how much you save and when. The best strategy is to go after the low-hanging fruit first as you're planning the bigger projects. A rain barrel system can go in tomorrow and start saving you money right away. Then, when your roof needs replacement in a few years, that's the perfect time to add the green roof component. The budget always plays into any property improvement choice, with green infrastructure being no exception. Atlanta property owners actually have access to something called PACE financing that spreads the cost over a few years instead of one massive check up front. These stormwater credits also pair nicely with other incentive programs, too. Georgia Power has rebates on different upgrades, while federal tax credits can help offset the final price tag for qualified installations.
Quite a few different options are available in Atlanta, and each one comes with a different level of savings. You need to plan everything out well before you start any roof work. You can't simply decide halfway through construction that you want these credits. The paperwork has to be ready and submitted before breaking ground.
The different strategies that are available work together and can multiply your total savings significantly. A green roof section that's paired with rainwater storage tanks gives you one type of system. Blue roof detention areas combined with traditional roofing materials give you a different strategy. Every combination creates its own system - and these systems pay for themselves quickly. The monthly fee reductions add up to serious money over time. When property owners run the numbers, they find that after just 5 to 7 years, they've already covered their entire investment through these monthly savings.
Atlanta's review process takes time, and you need to plan ahead for it. Submitting your paperwork late can push back your whole construction timeline. Back in 2023, the city expanded this program and created a lot more opportunities for property owners. Of course, with those extra opportunities come extra requirements and a lot more details to track. The most important number for you to know is what you're currently paying in stormwater fees. When you know what you're paying now, the savings become obvious. That number also tells you which improvements are actually worth doing for your property.
Colony Roofers specializes in commercial and residential roofing with headquarters throughout Georgia, Florida and Texas. We work with stormwater credit systems regularly, and we know how to design roofs that'll keep your building safe and your monthly fees low. Your roof deserves better than whoever shows up first with the cheapest quote. It's a big investment, and you need a team that knows what they're doing. Colony Roofers has the expertise and the track record to deliver quality repairs and installations that will last. Give us a call for a free inspection and to talk about all your options.