Storm Water Engineering Plan Review (Letter of Approval)


According to 18 AAC 72.600, storm water engineering plans should be submitted to DEC for review and approval. To obtain a "storm water letter of approval" an applicant must submit a copy the Permanent Storm Water Management Control Plan Review Checklist with all documents listed on the General Project Information page. See the Frequently Asked Questions for answers to the commonly asked questions.

The type of items that do need a letter of Approval include:

  • Dry Extended Detention Pond
  • Constructed Wetlands
  • Wet Ponds
  • Sand Filters
  • Oil/Grit Separators
  • Rotational Flow Separators
  • Constructed Snow Disposal Area
  • Storm Drain Collection Lines
  • Other similar treatment controls

The kinds of projects that typically do not need a letter of Approval (unless they use one of the treatment controls listed above) include:

  • Road maintenance (to maintain the original line and grade of ditches and running surfaces.)
  • Bike and Pedestrian Trails
  • Golf Courses
  • Boardwalks
  • Weigh Stations
  • Sewage Lagoons

There are two manuals that may be helpful in the design process and in filling out the comments on the permanent storm water management control plan review checklist. They are the DEC Alaska Storm Water Guide and the Municipality of Anchorage Project Management Engineering Department - Design Criteria Manual Chapter 2 Drainage, dated March 2015.


William Ashton, Storm Water and Wetlands Engineer
ADEC, Division of Water
555 Cordova Street
Anchorage, AK 99501
Office: 907-269-6283 | Fax 907-269-3487
Email Address: