Moody’s, Standard & Poor’s reaffirm Charleston Water System Triple-A bond ratings

June 18, 2020

Charleston Water System (CWS) earned the highest possible bond credit ratings from Moody’s Investors Service (Moody’s) at Aaa and S&P Global Ratings (S&P) at AAA on June 12, 2020. Both Triple-A ratings apply to CWS’s $119.6 million Series 2020A Taxable and 2020B Tax-exempt Waterworks and Sewer System Refunding & Capital Improvement Revenue Bonds. In addition, both research agencies also affirmed their Triple-A rating on the system’s existing revenue bonds along with giving a stable outlook. CWS initially received the S&P AAA rating in 2010 and Moody’s Aaa in 2015. Since those initial upgrades, the utility has had nine affirmations of this rating by S&P and seven affirmations by Moody’s. CWS is the only combined water and wastewater utility in South Carolina to hold a Triple-A rating from Moody’s.

These ratings reflect CWS’s sizeable, regionally important service area that is projected to experience continual growth, as well as low risk operations and very strong operational and financial management. High liquidity also played an important role in the top ratings.

Strong bond ratings help utilities market their bonds at the lowest interest rates possible, which helps to minimize water and sewer rate increases needed to repay debt. CWS operations are funded through water and sewer rates and fees, while the utility’s capital improvements program is funded through water and sewer rates, new development impact fees, and interest income.

The CWS 2019-2022 Capital Improvement Program consists of critical water and sewer infrastructure projects including:

  • Plum Island WWTP Phase 4 Improvements including updates to the Solids Handling Facility
  • Peninsula Trunk Main 3A – Phases 1 and 2
  • West Ashley Transmission Main
  • Water Main Replacements / Rehabilitation Program
  • Customer Service / IT / Emergency Operations Facility
  • John’s Island Wastewater Interceptor System Expansion –  Phase 3
  • Thomas Island Regional Pump Station and Sewer System – Phase 1
  • Gibson Raw Water Pump Station Improvements
  • Hanahan Water Treatment Plant Disinfectant Contact Basin
  • Ben Sawyer – Intracoastal Water Main Crossing
  • Pump Station and Collection System Rehabilitation

About Charleston Water System

Charleston Water System is a public water and wastewater utility that provides water service to more than 450,000 people in greater Charleston area and sewer service to 180,000 people, primarily in the city of Charleston. Learn more at