Exhibit 99.1

ADVANCED DRAINAGE SYSTEMS ANNOUNCES FIRST QUARTER FISCAL 2019 RESULTS

HILLIARD, Ohio – (August 9, 2018) – Advanced Drainage Systems, Inc. (NYSE: WMS) (“ADS” or the “Company”), a leading global manufacturer of water management products and solutions for non-residential, residential, infrastructure and agricultural applications, today announced financial results for the first fiscal quarter ended June 30, 2018.

First Quarter Fiscal 2019 Highlights

Scott Barbour, President and Chief Executive Officer of ADS commented, “We are very pleased with our strong start to the year, including solid top line growth driven by above-market growth in both non-residential and residential construction markets as well as strong performance from our International businesses. We also benefited from disciplined execution and growing demand for our allied products, which drove our third consecutive quarter of year over year margin expansion. With the backdrop of healthy expected growth in our core domestic construction markets for the remainder of fiscal 2019, we remain focused on executing our key growth strategies while continuing to take actions to mitigate inflationary pressure, increase profitability and drive shareholder value.”

First Quarter Fiscal 2018 Results

Net sales increased 8.2% to $387.8 million, as compared to $358.4 million in the prior year. Domestic net sales increased 7.2% to $342.5 million as compared to $319.5 million in the prior year, driven by strong demand and market conversion in the construction markets. International net sales increased 16.7% to $45.3 million as compared to $38.9 million in the prior year, driven by growth in Mexico and Canada.

Gross profit increased 14.9% to $99.7 million, as compared to $86.7 million the prior year quarter. As a percentage of net sales, gross profit increased 150 basis points to 25.7% compared to 24.2% in the prior year, primarily due to favorable pricing as well as lower manufacturing costs.

Adjusted EBITDA (Non-GAAP) increased 24.5% to $75.1 million, as compared to $60.3 million in the prior year quarter. As a percentage of net sales, Adjusted EBITDA increased 260 basis points to 19.4% as compared to 16.8% in the prior year. The increase in Adjusted EBITDA margin was largely attributed to the factors mentioned above as well as a decrease in selling, general and administrative expenses.

Net cash provided by operating activities increased $26.4 million to $9.8 million, as compared to a use of $16.5 million in the prior year. Free cash flow (Non-GAAP) increased $37.4 million to $3.0 million, as compared to a use of $34.5 million in the prior year. Net debt (total debt and capital lease obligations net of cash) was $366.0 million as of June 30, 2018, an increase of $3.8 million from March 31, 2018.

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.”

Fiscal Year 2019 Outlook

Based on current visibility, backlog of existing orders and business trends, the Company has provided its net sales and Adjusted EBITDA targets for fiscal 2019. Net sales are expected to be in the range of $1.375 billion to $1.425 billion, which is consistent with the Company’s previously issued guidance. The Company also is raising the bottom-end of its Adjusted EBITDA range by $5 million to an updated range of $225 to $240 million. Capital expenditures are expected to be approximately $60 to $70 million.

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Webcast Information

The Company will host an investor conference call and webcast on Thursday, August 9, 2018 at 10:00 a.m. Eastern Time. The live call can be accessed by dialing 1-866-393-4306 (US toll-free) or 1-734-385-2616 (international) and asking to be connected to the Advanced Drainage Systems, Inc. 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 the leading manufacturer of high performance thermoplastic corrugated pipe, providing a comprehensive suite of water management products and superior drainage solutions for use in the construction and infrastructure marketplace. Its innovative products are used across a broad range of end markets and applications, including non-residential, residential, agriculture and infrastructure 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 over 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, without limitation, 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; our ability to continue to convert current demand for concrete, steel and PVC pipe products into demand for our high performance thermoplastic corrugated pipe and Allied Products; the effect of weather or seasonality; the loss of any of our significant customers; the risks of doing business internationally; the risks of conducting a portion of our operations through joint ventures; our ability to expand into new geographic or product markets; 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; fluctuations in our effective tax rate, including from the recently enacted Tax Cuts and Jobs Act; changes to our operating results, cash flows and financial condition attributable to the recently enacted Tax Cuts and Jobs Act; 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 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

Director, Investor Relations and Business Strategy

(614) 658-0050

Mike.Higgins@ads-pipe.com

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Financial Statements

ADVANCED DRAINAGE SYSTEMS, INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF INCOME

(unaudited)

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ADVANCED DRAINAGE SYSTEMS, INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED BALANCE SHEETS

(unaudited)

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ADVANCED DRAINAGE SYSTEMS, INC. AND SUBSIDIARIES

CONDENSED 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

The impact of the ESOP on net 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.

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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 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 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 Adjusted EBITDA to Net Income

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Reconciliation of Segment Adjusted EBITDA to Net Income

Reconciliation of Free Cash Flow to Cash flow from Operating Activities