How to Use the Manual

When planning a project, this Manual is best used for addressing on-site stormwater mitigation, storage, and reuse associated with single-family residences. Multiple Low Impact Development (LID) stormwater management approaches can be used together to attain the required storage quantity and treatment quality that the Walton County Land development Code (LCD) and Comprehensive Plan requires.  This manual is organized so that each section is independent of the other. If you are not installing one of the LID stormwater management facilities (SWMFs) then you do not need to read the section pertaining to that approach.

In order to become familiar with the general concepts of site evaluation and the Walton County stormwater criteria, homeowners (or their representatives) need to read Section 1 through 3 to get started. Once you are acquainted with site evaluation and storage requirements you can either choose to use the EPA Stormwater Calculator; or you can choose the LID SWMF that most interests you and design it by hand. You also have the option to use a design spreadsheet available on the County website (Currently Under Construction), in this case you will turn to the specific section focusing on the LID(s) of your choice and familiarize yourself with the required input parameters

The following is a brief description of each section:

  • Section 1 introduces the concepts of LID SWMFs;
  • Section 2 guides the homeowner through the site evaluation process;
  • Section 3 provides guidance associated with stormwater treatment criteria;
  • Section 4 provides an in depth description of how to use the EPA National Stormwater Calculator (  
  • The National stormwater Calculator is free software designed to assist homeowners, landscapers, and local governments in expanding the use of green infrastructure. 
  • Section 5 presents a variety of LID stormwater management solutions along with a description of optimal site conditions, design considerations, and calculation examples that will assist in determining if the chosen LID SWMF is feasible for your property. 
  • Section 6 contains additional design considerations. 
  • Appendices – Plant recommendation, definitions, and precipitation tables.

LID SWMF Certification Form & Transfer of Ownership Form