Low Impact Development

Introduction Location Land Use Change : Selected Basic LID Lot Level LID Results Video Links

Land Use Change Scenarios

Users must identify the current land use for a specific area and can describe one land use change scenario. Users must also describe each land use description's size and soil type. Size can be entered in either acres, square miles, hectares, or square kilometers. If unknown, soil types can be determined using the link below to search GIS maps of your region. Help is available by clicking on any of the question mark icons. (Important: The total area of the current land use and each of the land use change scenarios must be equal before L-THIA can run).

STEP 1: Specify units for area : Select the desired units for describing land use area   Video 1

STEP 2: Enter the pre-developed land use and area

Land Use Choose the appropriate land uses from the pull-down menus below that best describe the property. Before selecting another land use, you will need to enter data in the are fields on the right. Lot Size If no value is selected, defaul lot size of 1/8 acre for High Density Residential and 1/2 acre for Low Density Residential will be used. Soil Type Select the hydrologic soil type (A, B, C, or D) that best describes the property. If unsure, click on the Check Map button below to identify the recommended soil type in the selected county. Pre-Developed Area Enter the units of area that identify the size of a particular land use. Users must provide data for the current field and can enter data for one land use change scenario. At the bottom of the table, the total area fields must be equal before L-THIA can run.
(Use as many as necessary) (in acres)  
  Total Area:

STEP 3: Enter the post-developed land use and area

  Land Use Choose the appropriate land uses from the pull-down menus below that best describe the property. Before selecting another land use, you will need to enter data in the are fields on the right. Lot Size If no value is selected, defaul lot size of 1/8 acre for High Density Residential and 1/2 acre for Low Density Residential will be used. Soil Type Select the hydrologic soil type (A, B, C, or D) that best describes the property. If unsure, click on the Check Map button below to identify the recommended soil type in the selected county. Post-Developed Area Enter the units of area that identify the size of a particular land use. Users must provide data for the current field and can enter data for one land use change scenario. At the bottom of the table, the total area fields must be equal before L-THIA can run.
  With LID
  (Use as many as necessary) (in acres) Total
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
  Total Area:

If you are manually entering land uses and wish to copy the values from the top table into the bottom table for easier editing, please press the button below. If you are using this from in conjunction with a map editor, values for all applicable fields should automatically be filled in. This may take a couple of seconds

STEP 4: Select the level of LID screening you wish to perform
Basic LID Screening
Lot Level LID Screening

L-THIA Home
L-THIA First Steps Basic Screening Model