Hawaii Administrative Rules › Title 13 - DEPARTMENT OF LAND AND NATURAL RESOURCES › Subtitle 1 - ADMINISTRATION › Chapter 5 - CONSERVATION DISTRICT › Exhibit 5 - Fire Buffer Zone Standards

Current through June, 2024
August 12, 2011
Design standards for creation and maintenance of fire buffer
				  zones along the urban/conservation interface. Fire buffer zones shall be
				  approved via site plan approval.
PURPOSE The goal of a fire buffer zone is to reduce the risk
				  of fire spreading to an area, and to reduce the speed at which fire spreads,
				  should one occur. This is accomplished by (1) reducing the amount of available
				  fuels, (2) reducing the continuity of available fuels, both horizontally
				  through the proper spacing of trees and shrubs, and vertically by removing the
				  ladder of fuels that can carry fire from the surface to the tree crowns, (3)
				  developing a high-canopy forest, (4) replacing highly-flammable flora with
				  drought and fire resistant indigenous, endemic, or Polynesian-introduced
				  species, and (5) encouraging community stewardship of lands in the Conservation
				  District.
APPLICATION REQUIREMENTS
* Parcel is considered a high-risk fire prone area by an
				  authority recognized by the department (e.g., Division of Forestry and
				  Wildlife, or the County Fire Department).
* If landscaping is to occur on neighboring parcels, the
				  applicant should have permission of the neighboring landowner. The chairperson
				  may sign as landowner for parcels owned by the State.
* A Site Plan should include three elements:
(1) location maps,
(2) an implementation plan, and
(3) a maintenance plan.
* Maps for the area should identify: topography, drainage
				  patterns, land ownership, dominant flora and fauna, trees greater than ten
				  inches in diameter measured at 4.5 feet above the ground, endangered and
				  threatened trees, and other indigenous, endemic, or Polynesian-introduced trees
				  or shrubs, infrastructure, and known historical or archaeological sites.
* The implementation plan should show the final design of the
				  fire protection zone, how impacts to endangered or threatened trees or shrubs,
				  or historical or archaeological sites will be mitigated.
* The management plan should discuss how and when the fire
				  protection zone will be maintained.
* The size of the fire buffer zone will be based upon the
				  slope of the area, as shown in Table 2. Distances are measured from the outside
				  of the main structure, as measured from the outside eaves and/or any attached
				  structures.
TABLE 2: AREA OF DEFENSIBLE SPACE
ZONE
SLOPE
DEFENSIBLE SPACE
1 Area of maximum reduction
all
0-15 feet
2 Area of fuel reduction
0-20%
15-30 feet
21-40%
15-50 feet
[GREATER THAN]40%
15-70 feet
3 Transition Zone
0-20%
30-75 feet
21-40%
50-100 feet
[GREATER THAN]40%
70-125 feet
DESIGN ELEMENTS
The following are acceptable design elements for each
				  zone:
Zone 1:
* Removal of all flammable vegetation.
* Pruning of existing trees to a height of ten feet above the
				  ground or to one-half the height of the tree, whichever is the lowest.
* Planting of drought and fire resistant indigenous, endemic,
				  or Polynesian-introduced trees and shrubs, along with associated soil
				  improvements and mulching.
* Removal of all ladder fuels beneath existing trees.
Zone 2:
* Thinning of trees and shrubs so that they stand solo, or in
				  clumps of two or three. Recommended space between crowns is based upon slope,
				  as summarized in Table 3.
TABLE 3: MINIMUM TREE AND SHRUB SPACING FOR ZONE
							 2
SLOPE
TREE CROWN SPACING
SHRUB CLUMP
SPACING
0-10%
10 feet
2½ x shrub height
11-20%
15 feet
3x shrub height
21-40%
20 feet
4x shrub height
[GREATER THAN]40%
30 feet
6x shrub height
* Removal of ladder fuels.
* Mowing or cutting grasses as needed to keep them at a
				  maximum height of 6-8 inches.
* Pruning of tree branches to a height of at least ten
				  feet.
* Replanting of drought and fire resistant indigenous,
				  endemic or Polynesian-introduced trees and shrubs, along with associated soil
				  improvements and mulching.
* Removal of dead trees.
* Annual maintenance thinning of trees as they grow in
				  size.
* Annual removal of dead stems and branches.
Zone 3:
* Thinning of trees, with spacing based upon the tree
				  diameter measured at 4.5 foot above the ground, as outlined in Table 4.
TABLE 4: MINIMUM TREE SPACING FOR ZONE 3
Tree Diameter (inches)
Average Stem Spacing (feet)
3
10
4
11
5
12
6
13
7
14
8
15
9
16
10
17
11
19
12
21
13
23
14
24
15
26
16
28
17
29
18
31
19
33
20
35
21
36
22
38
23
40
24
42
* Pruning of tree branches to a height of at least ten feet
				  along fire or access roads.
* Annual maintenance thinning as trees grow in size.
MAINTENANCE GUIDELINES
Zones 2 and 3 are subject to the following maintenance
				  guidelines:
* Any replanting should only be done with indigenous,
				  endemic, or Polynesian-introduced trees and shrubs.
* No grubbing or grading is allowed for this land use.
* Slash (limbs, branches, and other woody debris) should be
				  disposed of by removing it from site, chipping and distributing over the
				  ground, or lopping and scattering.
* Tree stumps should remain in the ground.
* Surface (drip) irrigation lines are allowed to support new
				  plantings.
* Applicant should provide the Office of Conservation and
				  Coastal Lands with photographs of completed work.