Exhibit 99.1

ADVANCED DRAINAGE SYSTEMS ANNOUNCES FIRST QUARTER FISCAL 2021 RESULTS

HILLIARD, Ohio – (August 6, 2020) – Advanced Drainage Systems, Inc. (NYSE: WMS) (“ADS” or the “Company”), a leading provider of innovative water management solutions in the stormwater and on-site septic waste water industries today announced financial results for the first quarter ended June 30, 2020.

First Quarter Fiscal 2021 Results

Scott Barbour, President and Chief Executive Officer of ADS commented, “We had a strong start to fiscal 2021 as demand and business activity remained stable overall in the first quarter, with underlying variability by geography and end market. Strong performance in key growth states like the Carolinas, Florida, the Southeast and Utah was partially offset early in the quarter by states that reduced construction activity due to the COVID pandemic. Additionally, we experienced a strong selling season in the domestic Agriculture market with 36% growth in the first quarter. As a whole, ADS benefitted from our national presence as well as our geographic and end market exposure, including the increased exposure to the Residential end market that Infiltrator provides.”

Barbour continued, “We also achieved record profitability in the first quarter. Organic* Adjusted EBITDA margin increased 830 basis points driven by favorable material cost, lower manufacturing and transportation costs driven by our operational initiatives, contributions from the proactive cost mitigation steps announced in March, and leverage from the sales growth in both pipe and Allied products. Consolidated Adjusted EBITDA margin increased 1200 basis points including the impact of the Infiltrator acquisition announced August 1, 2019. Infiltrator achieved record profitability in the quarter due to favorable material costs, the impact from our synergy programs and continued execution of their proven business model.”

Barbour concluded. “The second quarter continues similarly to the first quarter at both ADS and Infiltrator. Our order book, project tracking, book to bill ratio and backlog all remain positive year-over-year. We expect the normal seasonal patterns to apply as the year progresses. However, uncertainties exist regarding the future market environment. Disciplined execution and focusing on the basics are particularly important in the current market environment and we will be focused on these as we build on our strong start to fiscal 2021.”

First Quarter Fiscal 2021 Results

Net sales increased $94.9 million, or 22.9%, to $508.6 million, as compared to $413.7 million in the prior year. Domestic pipe sales increased $11.5 million, or 4.4%, to $273.7 million. Domestic allied products & other sales increased $4.7 million, or 4.2%, to $116.9 million. These increases were driven by growth in both the U.S. construction and agriculture end markets. Infiltrator Water Technologies contributed an additional $102.2 million to net sales in the quarter.

Gross profit increased $250.7 million to $188.5 million as compared to ($62.2) million in the prior year. The prior year gross profit includes $168.6 million of ESOP special dividend compensation expense. The remaining increase is primarily due to the acquisition of Infiltrator Water Technologies, favorable material cost, an increase in operational efficiency and increases in both pipe and allied product sales.

Adjusted EBITDA (Non-GAAP) increased $79.2 million, or 98.6%, to $159.5 million, as compared to $80.3 million in the prior year. The increase is primarily due to the factors mentioned above. Infiltrator Water Technologies contributed an additional $42.0 million to Adjusted EBITDA in the quarter. As a percentage of net sales, Adjusted EBITDA was 31.4% as compared to 19.4% in the prior year.

*Organic growth (Non-GAAP) excludes net sales growth from Infiltrator Water Technologies.

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Reconciliations of GAAP to Non-GAAP financial measures for Adjusted EBITDA and Free Cash Flow have been provided in the financial statement tables included in this press release. An explanation of these measures is also included below under the heading “Non-GAAP Financial Measures.”

Balance Sheet and Liquidity

Net cash provided by operating activities increased $70.9 million, or 112.8%, to $133.7 million, as compared to $62.8 million in the prior year, primarily due to the increase in profitability. Free cash flow (Non-GAAP) increased $70.3 million, or 132.4%, to $123.4 million, as compared to $53.1 million in the prior year. Net debt (total debt and finance lease obligations net of cash) was $870.4 million as of June 30, 2020, a decrease of $117.6 million from March 31, 2020.

ADS had total liquidity of $524 million, comprised of cash of $235 million as of June 30, 2020 and $289 million of availability under committed credit facilities. As of June 30, 2020, the Company’s leverage ratio was 1.9 times on a trailing-twelve-month, proforma basis (2.0 times on a reported basis).

Fiscal 2021 Outlook

ADS continues to carefully monitor the pandemic and the impact on its business. However, given the market uncertainty, the Company is currently unable to predict the extent to which the pandemic will impact future operations and financial results and therefore is not issuing financial guidance at this time. In fiscal 2021, capital expenditures are expected to be in the range of $60 million to $65 million.

Webcast Information

Participants may Register Here for this conference call or copy and paste the following text into your browser: http://www.directeventreg.com/registration/event/5793176. After registering, participants will receive a confirmation through email, including dial in details and unique conference call codes for entry. Registration is open through the live call. To ensure participants are connected for the full call, please register at least 10 minutes before the start of the call. The live webcast will also be accessible via the "Events Calendar” section of the Company’s Investor Relations website, www.investors.ads-pipe.com. An archived version of the webcast will be available for one year following the call.

About the Company

Advanced Drainage Systems is a leading provider of innovative water management solutions in the stormwater and on-site septic wastewater industries, providing superior drainage solutions for use in the construction and agriculture marketplace. For over 50 years, the Company has been manufacturing a variety of innovative and environmentally friendly alternatives to traditional materials. Its innovative products are used across a broad range of end markets and applications, including non-residential, residential, infrastructure and agriculture applications. The Company has established a leading position in many of these end markets by leveraging its national sales and distribution platform, overall product breadth and scale and manufacturing excellence. Founded in 1966, the Company operates a global network of approximately 60 manufacturing plants and 30 distribution centers. To learn more about ADS, please visit the Company’s website at www.ads-pipe.com.

Forward Looking Statements

Certain statements in this press release may be deemed to be forward-looking statements. These statements are not historical facts but rather are based on the Company’s current expectations, estimates and projections regarding the Company’s business, operations and other factors relating thereto. Words such as “may,” “will,” “could,” “would,” “should,” “anticipate,” “predict,” “potential,” “continue,” “expects,” “intends,” “plans,” “projects,” “believes,” “estimates,” “confident” and similar expressions are used to identify these forward-looking statements. Factors that could cause actual results to differ from those reflected in forward-looking statements relating to our operations and business include: fluctuations in the price and availability of resins and other raw materials and our ability to pass any increased costs of raw materials on to our customers in a timely manner; volatility in general business and economic conditions in the markets in which we operate, including the adverse impact on the U.S. and global economy of the COVID-19 global pandemic, and the impact of COVID-19 in the near, medium and long-term on our business, results of operations, financial position, liquidity or cash flows, and other factors relating to availability of credit, interest rates, fluctuations in capital and business and consumer confidence; cyclicality and seasonality of the non-residential and residential construction markets and infrastructure spending; the risks of increasing competition in our existing and future markets, including competition from both manufacturers of high performance thermoplastic corrugated pipe and manufacturers of products using alternative materials; uncertainties surrounding the integration of acquisitions and similar transactions, including the acquisition of Infiltrator Water Technologies and the integration of Infiltrator Water Technologies; our ability to realize the anticipated benefits from the acquisition of Infiltrator Water Technologies; risks that the acquisition of Infiltrator Water Technologies and related transactions may involve unexpected costs, liabilities or delays;

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our ability to continue to convert current demand for concrete, steel and polyvinyl chloride (“PVC”) pipe products into demand for our high performance thermoplastic corrugated pipe and Allied Products; the effect of any claims, litigation, investigations or proceedings; the effect of weather or seasonality; the loss of any of our significant customers; the risks of doing business internationally; our ability to remediate the material weakness in our internal control over financial reporting, including remediation of the control environment for our joint venture affiliate ADS Mexicana, S.A. de C.V.; the risks of conducting a portion of our operations through joint ventures; our ability to expand into new geographic or product markets, including risks associated with new markets and products associated with our recent acquisition of Infiltrator Water Technologies; our ability to achieve the acquisition component of our growth strategy; the risk associated with manufacturing processes; our ability to manage our assets; the risks associated with our product warranties; our ability to manage our supply purchasing and customer credit policies; the risks associated with our self-insured programs; our ability to control labor costs and to attract, train and retain highly-qualified employees and key personnel; our ability to protect our intellectual property rights; changes in laws and regulations, including environmental laws and regulations; our ability to project product mix; the risks associated with our current levels of indebtedness, including borrowings under our existing credit agreement and outstanding indebtedness under our existing senior notes; fluctuations in our effective tax rate; our ability to meet future capital requirements and fund our liquidity needs; the risk that additional information may arise that would require the Company to make additional adjustments or revisions or to restate the financial statements and other financial data for certain prior periods and any future periods; any delay in the filing of any filings with the Securities and Exchange Commission (“SEC”); the review of potential weaknesses or deficiencies in the Company’s disclosure controls and procedures, and discovering weaknesses of which we are not currently aware or which have not been detected; additional uncertainties related to accounting issues generally; and the other risks and uncertainties described in the Company’s filings with the SEC. New risks and uncertainties emerge from time to time and it is not possible for the Company to predict all risks and uncertainties that could have an impact on the forward-looking statements contained in this press release. In light of the significant uncertainties inherent in the forward-looking information included herein, the inclusion of such information should not be regarded as a representation by the Company or any other person that the Company’s expectations, objectives or plans will be achieved in the timeframe anticipated or at all. Investors are cautioned not to place undue reliance on the Company’s forward-looking statements and the Company undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

For more information, please contact:

Michael Higgins

VP, Corporate Strategy & Investor Relations

(614) 658-0050

[email protected]

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Financial Statements

ADVANCED DRAINAGE SYSTEMS, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF INCOME

(unaudited)

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ADVANCED DRAINAGE SYSTEMS, INC. AND SUBSIDIARIES

CONSOLIDATED BALANCE SHEETS

(unaudited)

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ADVANCED DRAINAGE SYSTEMS, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF CASH FLOWS

(unaudited)

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Selected Financial Data

The following tables set forth net sales by reportable segment for each of the periods indicated.

Employee Stock Ownership Plan (“ESOP”)

The Company established an ESOP to enable employees to acquire stock ownership in ADS in the form of redeemable convertible preferred shares (“preferred shares”). All preferred shares will be converted to common shares by plan maturity, which will be no later than March 2023. The ESOP’s conversion of preferred shares into common shares will have a meaningful impact on net income, net income per share and common shares outstanding. The common shares outstanding will be greater after conversion.

Net Income (Loss)

The impact of the ESOP on net (loss) income includes the ESOP deferred compensation attributable to the preferred shares allocated to employee accounts during the period, which is a non-cash charge to our earnings and not deductible for income tax purposes.

Common shares outstanding

The conversion of the preferred shares will increase the number of common shares outstanding. Preferred shares will convert to common shares at plan maturity, or upon retirement, disability, death or vested terminations over the life of the plan.

Non-GAAP Financial Measures

This press release contains financial information determined by methods other than in accordance with accounting principles generally accepted in the United States of America (“GAAP”). ADS management uses non-GAAP measures in its analysis of the Company’s performance. Investors are encouraged to review the reconciliation of non-GAAP financial measures to the comparable GAAP results available in the accompanying tables.

Reconciliation of Non-GAAP Financial Measures

This press release includes references to organic results, Adjusted EBITDA and Free Cash Flow, non-GAAP financial measures. These non-GAAP financial measures are used in addition to and in conjunction with results presented in accordance with GAAP. These measures are not intended to be substitutes for those reported in accordance with GAAP. Adjusted EBITDA and Free Cash

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Flow may be different from non-GAAP financial measures used by other companies, even when similar terms are used to identify such measures.

EBITDA and Adjusted EBITDA are non-GAAP financial measures that comprise net income before interest, income taxes, depreciation and amortization, stock-based compensation, non-cash charges and certain other expenses. The Company’s definition of Adjusted EBITDA may differ from similar measures used by other companies, even when similar terms are used to identify such measures. Adjusted EBITDA is a key metric used by management and the Company’s board of directors to assess financial performance and evaluate the effectiveness of the Company’s business strategies. Accordingly, management believes that Adjusted EBITDA provides useful information to investors and others in understanding and evaluating our operating results in the same manner as the Company’s management and board of directors. In order to provide investors with a meaningful reconciliation, the Company has provided below reconciliations of Adjusted EBITDA to net income.

Free Cash Flow is a non-GAAP financial measure that comprises cash flow from operating activities less capital expenditures. Free Cash Flow is a measure used by management and the Company’s board of directors to assess the Company’s ability to generate cash.  Accordingly, management believes that Free Cash Flow provides useful information to investors and others in understanding and evaluating our ability to generate cash flow from operations after capital expenditures. In order to provide investors with a meaningful reconciliation, the Company has provided below a reconciliation of cash flow from operating activities to Free Cash Flow.

The following tables present a reconciliation of EBITDA and Adjusted EBITDA to Net Income and Free Cash Flow to Cash Flow from Operating Activities, the most comparable GAAP measures, for each of the periods indicated.

Reconciliation of Segment Adjusted Gross Profit to Gross profit

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Reconciliation of Adjusted EBITDA to Net Income

Reconciliation of Segment Adjusted EBITDA

Reconciliation of Free Cash Flow to Cash flow from Operating Activities

Advanced Drainage Systems Q1 Fiscal 2021 Financial Results

Management Presenters Scott Barbour President and Chief Executive Officer Scott Cottrill Executive Vice President, Chief Financial Officer Mike Higgins Vice President, Corporate Strategy & Investor Relations

Forward Looking Statements and Non-GAAP Financial Metrics Certain statements in this presentation may be deemed to be forward-looking statements. These statements are not historical facts but rather are based on the Company’s current expectations, estimates and projections regarding the Company’s business, operations and other factors relating thereto. Words such as “may,” “will,” “could,” “would,” “should,” “anticipate,” “predict,” “potential,” “continue,” “expects,” “intends,” “plans,” “projects,” “believes,” “estimates,” “confident” and similar expressions are used to identify these forward-looking statements. Factors that could cause actual results to differ from those reflected in forward-looking statements relating to our operations and business include: fluctuations in the price and availability of resins and other raw materials and our ability to pass any increased costs of raw materials on to our customers in a timely manner; volatility in general business and economic conditions in the markets in which we operate, including the adverse impact on the U.S. and global economy of the COVID-19 global pandemic, and the impact of COVID-19 in the near, medium and long-term on our business, results of operations, financial position, liquidity or cash flows, and other factors relating to availability of credit, interest rates, fluctuations in capital and business and consumer confidence; cyclicality and seasonality of the non-residential and residential construction markets and infrastructure spending; the risks of increasing competition in our existing and future markets, including competition from both manufacturers of high performance thermoplastic corrugated pipe and manufacturers of products using alternative materials; uncertainties surrounding the integration of acquisitions and similar transactions, including the acquisition of Infiltrator Water Technologies and the integration of Infiltrator Water Technologies; our ability to realize the anticipated benefits from the acquisition of Infiltrator Water Technologies; risks that the acquisition of Infiltrator Water Technologies and related transactions may involve unexpected costs, liabilities or delays; our ability to continue to convert current demand for concrete, steel and polyvinyl chloride (“PVC”) pipe products into demand for our high performance thermoplastic corrugated pipe and Allied Products; the effect of any claims, litigation, investigations or proceedings; the effect of weather or seasonality; the loss of any of our significant customers; the risks of doing business internationally; our ability to remediate the material weakness in our internal control over financial reporting, including remediation of the control environment for our joint venture affiliate ADS Mexicana, S.A. de C.V.; the risks of conducting a portion of our operations through joint ventures; our ability to expand into new geographic or product markets, including risks associated with new markets and products associated with our recent acquisition of Infiltrator Water Technologies; our ability to achieve the acquisition component of our growth strategy; the risk associated with manufacturing processes; our ability to manage our assets; the risks associated with our product warranties; our ability to manage our supply purchasing and customer credit policies; the risks associated with our self-insured programs; our ability to control labor costs and to attract, train and retain highly-qualified employees and key personnel; our ability to protect our intellectual property rights; changes in laws and regulations, including environmental laws and regulations; our ability to project product mix; the risks associated with our current levels of indebtedness, including borrowings under our existing credit agreement and outstanding indebtedness under our existing senior notes; fluctuations in our effective tax rate; our ability to meet future capital requirements and fund our liquidity needs; the risk that additional information may arise that would require the Company to make additional adjustments or revisions or to restate the financial statements and other financial data for certain prior periods and any future periods; any delay in the filing of any filings with the Securities and Exchange Commission (“SEC”); the review of potential weaknesses or deficiencies in the Company’s disclosure controls and procedures, and discovering weaknesses of which we are not currently aware or which have not been detected; additional uncertainties related to accounting issues generally; and the other risks and uncertainties described in the Company’s filings with the SEC. New risks and uncertainties emerge from time to time and it is not possible for the Company to predict all risks and uncertainties that could have an impact on the forward-looking statements contained in this press release. In light of the significant uncertainties inherent in the forward-looking information included herein, the inclusion of such information should not be regarded as a representation by the Company or any other person that the Company’s expectations, objectives or plans will be achieved in the timeframe anticipated or at all. Investors are cautioned not to place undue reliance on the Company’s forward-looking statements and the Company undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

1 2 3 4 5 Q1 Fiscal 2021 Revenue Highlights Consolidated net sales grew 23% driven by 3% organic growth and contribution from Infiltrator Water Technologies. Organic domestic sales growth driven by key sales programs, as we continue to execute on material conversion, water management solutions and key growth states. Geographic and end market diversification contributed to overall growth, with 13% growth in residential sales and 36% growth in agriculture sales. Infiltrator Water Technologies results exceeded expectations, driven by growth across the product portfolio as well as strong demand in both residential and repair/remodel end markets. Demand and business activity remain stable into the second quarter, though future demand remains uncertain. Q1 FY21 Domestic End Market Sales Mix

1 2 3 4 Q1 Fiscal 2021 Highlights Consolidated Adjusted EBITDA increased 99%, driven by 47% increase in the legacy ADS business and contribution from Infiltrator Water Technologies. Organic Adjusted EBITDA growth driven by favorable material cost, lower manufacturing/transportation costs, contributions from the proactive cost mitigation steps and leverage from the sales growth in both pipe and Allied products. Infiltrator profitability driven by favorable material costs, impact from synergy programs and continued execution of proven business model. Trailing-twelve-month proforma leverage of 1.9x is favorable, one full turn and six months ahead of acquisition plan.

Q1 Fiscal 2021 Financial Performance +1200 bps Organic* +830 bps (USD, in millions) +22.9% Organic* +3.1% By Application + Pipe +4% + Allied +4% Domestic Markets + Construction +2% ‒ Non-Residential - 3% + Residential +13% + Infrastructure +5% + Agriculture +36% Organic* Revenue Performance By Geography + Domestic +4% + Pipe +4% + Allied +4% ‒ International - 9% ‒ Pipe - 8% ‒ Allied - 12% $80.3 $8.6 $17.1 ($1.7) $42.0 $159.5 Revenue Adj. EBITDA *Organic results represent the legacy ADS business and exclude Infiltrator Water Technologies results. $13.6 $509 $414 $426* 31.4% 19.4% 27.7%* +$37.6M ($0.4)

Free Cash Flow   FY 2021 FY 2020 ∆ Consolidated Adjusted EBITDA $159 $80 $79 Working capital(2) (9) (8) (1) Cash tax (0) (1) 1 Cash interest (7) (3) (4) Transaction costs(3) ‒ (1) 1 Other (9) (4) (5) Consolidated Cash flow from operations $134 $63 $71 Capital expenditures (10) (10) 0 Consolidated Free cash flow $124 $53 $71 Free Cash Flow (¹) Note: all figures in USD, $mm. Figures may not add due to rounding. Operating Cash Flow less CapEx Inventory, Trade Receivables, Accounts Payable Advisory, legal, and consulting fees related to acquisition of Infiltrator Water Technologies

Capital Structure & Liquidity  (in millions) June 30, 2020 March 31, 2020 Interest Term Loan Facility (9/2019) $ 647 $ 648 L + 2.250% Senior Notes (9/2019) 350 350 5.000% Revolving Credit Facility 50 100 L + 2.000% Equipment financing 1 1 2.753% Total debt $ 1,048 $ 1,099 Finance leases $ 60 $ 65 5.565% Leverage 2.0 times 2.7 times TTM Proforma Leverage 1.9 times 2.5 times Debt & Capital Leases Maturity Profile $300M(1) $647M(2) $350M Balance sheet and liquidity position remain strong; no significant maturities until 2026 Includes letters of credit outstanding of $11 million. Term Loan Facility amortizes at a rate of 1% per year until maturity.  (in millions) June 30, 2020 Cash $ 235 Availability under Revolving Credit Facility 289 Total Liquidity $ 524 Liquidity $50M

Q&A Session

1 2 3 4 5 Closing Remarks Employee health and safety will remain our highest priority. ADS and Infiltrator continue to provide essential water management and on-site septic solutions to the customers and the communities they serve. Trailing-twelve-month proforma leverage of 1.9x is favorable, one full turn and six months ahead of acquisition plan. Project quotes, order rate and backlog remain positive year-over-year. Expect normal seasonal patterns to apply as year progresses. Focused on disciplined execution and the basics as we build on strong start to fiscal 2021.

Appendix

Q1 FY 2021 Infiltrator Water Technologies Results Infiltrator Water Technologies results performed above previous expectations Infiltrator Water Technologies acquisition closed July 31, 2019. (1) Includes $18.1 million of intersegment net sales for the three months ended June 30, 2020. (USD, in millions) $102(1) Revenue Adj. EBITDA Revenue Ahead of expectations Strong growth across product portfolio as Infiltrator Water Technologies continues to drive conversion from traditional materials in on-site septic systems Capitalized on strong housing and repair/remodel market Solid growth across domestic footprint Integration On track to achieve targeted 3-year synergies (USD, in millions) $42

Reconciliations Three Months Ended June 30, (Amounts in thousands) 2020 2019 Segment Adjusted Gross Profit       Pipe $ 90,599 $ 57,493 International 11,408   9,227 Infiltrator Water Technologies 47,928 - Allied Products & Other 60,468   57,187 Intersegment Elimination (358) - Total Segment Adjusted Gross Profit 210,045   123,907 Depreciation and amortization 16,423 13,684 ESOP and stock-based compensation expense 4,939   3,771 ESOP special dividend compensation - 168,610 COVID-19 related expenses 180   - Total Gross Profit $ 188,503   $ (62,158) Three Months Ended June 30, 2020 June 30, 2019 Net Sales Intersegment Net Sales Net Sales from External Customers Net Sales Intersegment Net Sales Net Sales from External Customers Pipe $ 273,652 $ (1,845) $ 271,807 $ 62,181 $ — $ 262,181 Infiltrator Water Technologies 102,153 (18,068) 84,085 — — — International International - Pipe 26,950 — 26,950 29,284 — 29,284 International - Allied Products 8,879 — 8,879 10,049 — 10,049 Total International 35,829 — 35,829 39,333 — 39,333 Allied Products & Other 116,918 — 116,918 112,194 — 112,194 Intersegment Eliminations (19,913) 19,913 — — — — Total Consolidated $ 508,639 $ — $ 508,639 $ 413,708 $ — $ 413,708

Reconciliations Includes expenses directly related to our response to the COVID-19 pandemic, including adjustments to our pandemic pay program and expenses associated with our 3rd party crisis management vendor. Includes derivative fair value adjustments, foreign currency transaction (gains) losses, the proportionate share of interest, income taxes, depreciation and amortization related to the South American Joint Venture, which is accounted for under the equity method of accounting and executive retirement expense. The other adjustments in fiscal 2020 also includes expenses related to the ADS Mexicana’s investigation. Three Months Ended June 30, (Amounts in thousands) 2020 2019 Net income (loss) $ 70,668   $ (227,451) Depreciation and amortization 35,781 16,694 Interest expense 9,970   5,264 Income tax expense 27,200 22,370 EBITDA 143,619   (183,123) Loss on disposal of assets and costs from exit and disposal activities 1,647 707 ESOP and stock-based compensation expense 12,462   7,425 ESOP special dividend compensation - 246,752 Transaction costs 656   4,245 Strategic growth and operational improvement initiatives 1,755 2,195 COVID-19 related expenses (a) 564   - Other adjustments(b) (1,233) 2,095 Adjusted EBITDA $ 159,470   $ 80,296 Three Months Ended June 30, (Amounts in thousands) 2020 2019 Legacy ADS Adjusted EBITDA       Pipe Adjusted Gross Profit $ 90,599 $ 57,493 International Adjusted Gross Profit 11,408   9,227 Allied Products & Other Adjusted Gross Profit 60,468 57,187 Unallocated corporate and selling expenses (44,644)   (43,611) Legacy ADS Adjusted EBITDA 117,831 80,296 Legacy Infiltrator Water Technologies Adjusted EBITDA       Infiltrator Water Technologies 47,928 - Unallocated corporate and selling expenses (5,931)   - Legacy Infiltrator Water Technologies Adjusted EBITDA $ 41,997 $ - Intersegment Eliminations (358)   - Consolidated Adjusted EBITDA $ 159,470 $ 80,296

Exhibit 99.3

ADVANCED DRAINAGE SYSTEMS ANNOUNCES QUARTERLY CASH DIVIDEND

HILLIARD, Ohio – (August 6, 2020) – Advanced Drainage Systems, Inc. (NYSE: WMS) (“ADS” or the “Company”), a leading provider of innovative water management solutions in the stormwater and on-site septic waste water industries, today announced that its Board of Directors has approved a quarterly cash dividend to its shareholders in the amount of $0.09 per share.

Scott Barbour, President and Chief Executive Officer of Advanced Drainage Systems commented, “Today’s dividend demonstrates our commitment to returning capital to shareholders, as well as our confidence in the strength of our balance sheet to be able to return this cash to shareholders while also continuing to invest in our business and strategic initiatives of the Company.”  

The quarterly cash dividend of $0.09 per share will be paid on September 15, 2020 to shareholders of record at the close of business on September 1, 2020.

About the Company

Advanced Drainage Systems is a leading provider of innovative water management solutions in the stormwater and on-site septic wastewater industries, providing superior drainage solutions for use in the construction and agriculture marketplace. For over 50 years, the Company has been manufacturing a variety of innovative and environmentally friendly alternatives to traditional materials. Its innovative products are used across a broad range of end markets and applications, including non-residential, residential, infrastructure and agriculture applications. The Company has established a leading position in many of these end markets by leveraging its national sales and distribution platform, overall product breadth and scale and manufacturing excellence. Founded in 1966, the Company operates a global network of approximately 60 manufacturing plants and 30 distribution centers. To learn more about ADS, please visit the Company’s website at www.ads-pipe.com.

Forward Looking Statements

Certain statements in this press release may be deemed to be forward-looking statements. These statements are not historical facts but rather are based on the Company’s current expectations, estimates and projections regarding the Company’s business, operations and other factors relating thereto. Words such as “may,” “will,” “could,” “would,” “should,” “anticipate,” “predict,” “potential,” “continue,” “expects,” “intends,” “plans,” “projects,” “believes,” “estimates,” “confident” and similar expressions are used to identify these forward-looking statements. Factors that could cause actual results to differ from those reflected in forward-looking statements relating to our operations and business include: fluctuations in the price and availability of resins and other raw materials and our ability to pass any increased costs of raw materials on to our customers in a timely manner; volatility in general business and economic conditions in the markets in which we operate, including the adverse impact on the U.S. and global economy of the COVID-19 global pandemic, and the impact of COVID-19 in the near, medium and long-term on our business, results of operations, financial position, liquidity or cash flows, and other factors relating to availability of credit, interest rates, fluctuations in capital and business and consumer confidence; cyclicality and seasonality of the non-residential and residential construction markets and infrastructure spending; the risks of increasing competition in our existing and future markets, including competition from both manufacturers of high performance thermoplastic corrugated pipe and manufacturers of products using alternative materials; uncertainties surrounding the integration of acquisitions and similar transactions, including the acquisition of Infiltrator Water Technologies and the integration of Infiltrator Water Technologies; our ability to realize the anticipated benefits from the acquisition of Infiltrator Water Technologies; risks that the acquisition of Infiltrator Water Technologies and related transactions may involve unexpected costs, liabilities or delays; our ability to continue to convert current demand for concrete, steel and polyvinyl chloride (“PVC”) pipe products into demand for our high performance thermoplastic corrugated pipe and Allied Products; the effect of any claims, litigation, investigations or proceedings; the effect of weather or seasonality; the loss of any of our significant customers; the risks of doing business internationally; our ability to remediate the material weakness in our internal control over financial reporting, including remediation of the control environment for our joint venture affiliate ADS Mexicana, S.A. de C.V.; the risks of conducting a portion of our operations through joint ventures; our ability to expand into new geographic or product markets, including risks associated with new markets and products associated with our recent acquisition of Infiltrator Water Technologies; our ability to achieve the acquisition component of our growth strategy; the risk associated with manufacturing processes; our ability to manage our assets; the risks associated with our product warranties; our ability to manage our supply purchasing and customer credit policies; the risks associated with our self-insured programs; our ability to control labor costs and to attract, train and retain highly-qualified employees and key personnel; our ability to protect our intellectual property rights; changes in laws and regulations, including environmental laws and regulations; our ability to project product mix; the risks associated with our current levels of indebtedness, including borrowings under our existing credit agreement and outstanding indebtedness under our existing senior notes; fluctuations in our effective tax rate; our ability to meet future capital requirements and fund our liquidity needs; the risk that additional information may arise that would require the Company to make additional adjustments or revisions or to restate the financial statements and other financial data for certain prior periods and any future periods; any delay in the filing of any filings with the Securities and Exchange Commission (“SEC”); the review of potential weaknesses or deficiencies in the Company’s disclosure controls and

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procedures, and discovering weaknesses of which we are not currently aware or which have not been detected; additional uncertainties related to accounting issues generally; and the other risks and uncertainties described in the Company’s filings with the SEC. New risks and uncertainties emerge from time to time and it is not possible for the Company to predict all risks and uncertainties that could have an impact on the forward-looking statements contained in this press release. In light of the significant uncertainties inherent in the forward-looking information included herein, the inclusion of such information should not be regarded as a representation by the Company or any other person that the Company’s expectations, objectives or plans will be achieved in the timeframe anticipated or at all. Investors are cautioned not to place undue reliance on the Company’s forward-looking statements and the Company undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

For more information, please contact:

Michael Higgins

VP, Corporate Strategy & Investor Relations

(614) 658-0050

[email protected]