Chapter 18.57
TREE MANAGEMENT AND PROTECTION

Sections:

18.57.010    Title.

18.57.015    Findings and purpose.

18.57.030    Applicability.

18.57.035    Exemptions.

18.57.050    Tree protection plan required.

18.57.060    Tree density requirement.

18.57.070    Tree protection plan review procedure.

18.57.080    Tree protection plan review standards.

18.57.085    Tree windthrow evaluation and prevention.

18.57.090    Tree protection during construction.

18.57.100    Post-construction replacement, financial guarantee and maintenance requirements.

18.57.110    Penalties, enforcement.

18.57.010 Title.

This chapter shall be known and may be cited as the Kenmore tree management and protection code. [Ord. 11-0329 § 3 (Exh. 1).]

18.57.015 Findings and purpose.

A. Reducing soil erosion and water pollution in the City’s streams and creeks by providing wind breaks, slowing the surface movement of water, reducing the amount of stormwater runoff, and stabilizing soil with their roots and fallen leaves;

B. Improving air quality by removing pollutant gases and airborne particles;

C. Positively affecting energy and water conservation by providing shade, lowering temperatures, and reducing net evaporation rates;

D. Reducing noise pollution by absorbing and deadening excessive and/or unwanted noise and by screening the source of the noise from view; and

E. Providing a wide variety of habitats and ecosystems for birds, mammals, and other wildlife;

F. Accordingly, the purpose of this chapter is to establish a process and standards to:

1. Increase the livability of an area by helping to screen people and buildings from wind and inclement weather;

2. Create a special sense of identity, a sense of community and civic pride, and a memorable place to live and work;

3. Preserve and enhance the City’s physical and aesthetic character by preventing untimely and indiscriminate removal or destruction of trees;

4. Promote site planning, construction practices, and horticultural practices that are consistent with the reasonable use of property;

5. Implement the goals and objectives of the City’s comprehensive plan; and

6. Implement the goals and objectives of the City’s parks and recreation master plan. [Ord. 11-0329 § 3 (Exh. 1).]

18.57.030 Applicability.

A. No individual, partnership, corporation, association, organization, cooperative, public or municipal corporation, or agency of any governmental unit, however designated, shall directly or indirectly remove or destroy any tree as defined in this title within the City, without first obtaining a clearing permit as provided in KMC Title 15.

B. Unless otherwise exempted in KMC 18.57.035, any site subject to development, including the division of a parcel of land into two or more parcels, within the City shall comply with the requirements of this chapter.

C. Approval of a tree protection plan pursuant to the provisions of this chapter shall not discharge the obligation of the applicant to otherwise comply with the applicable provisions of this chapter.

D. When any provision of any other chapter of the Kenmore Municipal Code conflicts with this chapter or when the provisions of this chapter are in conflict, that provision which provides more protection for individual trees and groves of trees shall apply unless specifically provided otherwise in this chapter or unless such provision conflicts with federal or State laws or regulations. [Ord. 11-0329 § 3 (Exh. 1).]

18.57.035 Exemptions.

A. The following land uses are exempt from the provisions of this chapter. However, compliance with other applicable provisions of the Kenmore Municipal Code including but not limited to then-current critical area regulations per Chapter 18.55 KMC and then-current clearing regulations per Chapter 15.25 KMC is still required:

1. Agriculture, meaning the use of the land for the primary purpose of deriving income from growing plants or trees on land including, but not limited to, land used principally for fruit or timber production, but not including land used principally for another use and only incidentally for growing trees or plants for income.

2. Commercial nursery or tree farm, but only those trees which are planted and growing on the premises of a licensed retailer or wholesaler for sale to the general public. Other trees on such premises shall remain subject to this chapter.

3. Residential Development.

a. All existing lots on which are to be situated new single detached dwelling units in residential zones based on tree removal limits established by clearing requirements.

b. All existing lots on which are situated existing detached dwelling units in residential zones based on tree removal limits established by clearing requirements.

4. Downtown Commercial and Downtown Residential Zones. All development occurring within core areas designated as downtown commercial and downtown residential zones. [Ord. 11-0329 § 3 (Exh. 1).]

18.57.050 Tree protection plan required.

A. Requirement Established. Except for the exemptions enumerated in this chapter, no individual, partnership, corporation, association, organization, cooperative, public or municipal corporation, or agency of any governmental unit, however designated, shall remove, transplant, or destroy, or cause to be removed, transplanted, or destroyed, on any land in the City, any tree as defined in this chapter, without first obtaining the city manager’s approval of a tree protection plan and receiving a clearing permit from the City. For sites proposed for land development, including the division of a parcel of land into two or more parcels, having trees below the minimum tree density, even though no trees are proposed to be removed, a tree protection plan is required to bring the site up to the minimum tree density standard herein established.

B. Submittal of Tree Protection Plan. Where the site proposed for development requires site or plat or short plat review, the tree protection plan shall be submitted concurrent with a site plan or plat or short plat application.

C. Tree Protection Plan Requirements. Attached to the applicant information and site plan information required for the clearing permit applications, the applicant shall include the following tree protection plan information:

1. Tree Survey. For all development proposals, a tree survey, drawn to scale by a land surveyor licensed in Washington State, identifying the exact location and conditions of existing trees as defined in this title and containing the following information:

a. Common and botanical name of each tree.

b. Trees proposed to remain and to be removed.

c. Groves with indication of predominant species, number of trees and size of d.b.h.

d. Any off-site tree with a root protection zone which could be adversely affected by the proposed activity.

e. The location and dimensions of established and proposed perimeter landscaping, natural vegetation easements, and open space areas for public, private, or community use.

f. Net buildable areas.

g. Critical areas and their buffers.

h. Stormwater tracts.

i. Limits of construction line.

j. North arrow, scale, and date of survey.

2. An assessment of tree windthrow potential as described in KMC 18.57.085, along with any proposed mitigation measures to minimize windthrow. These measures shall be incorporated into the proposed tree protection plan described in subsection (C)(5) of this section.

3. A statement describing how trees intended to remain will be identified, marked, and protected before the start of and during development as further described in KMC 18.57.090.

4. A statement that describes replacement tree quality as conforming to the American Standards for Nursery Stock (ANSI).

5. Proposed Tree Protection Plan. The permit applicant shall have a qualified tree protection professional prepare recommendations for the tree protection plan. The tree protection plan shall be drawn to scale using the tree survey as a base and containing the following information:

a. The exact location and conditions of protected trees.

b. The exact location, common name, botanical name, and caliper of each tree species to be planted.

c. The site minimum tree density calculation indicating the total number, size, and species of existing trees to be preserved and the replacement trees to be planted as described in KMC 18.57.060.

d. The site replacement tree calculation as described in KMC 18.57.060 with an explanation including the number, caliper, and species.

e. The location, materials, dimensions, and layout of the protective barriers.

6. Submit a landscape bond quantity form.

7. Additional Information. Any additional or more detailed information required by the city manager to ensure compliance with the provisions of this chapter (i.e., aerial photograph). The city manager may waive the requirements for the scaled drawing and other submission data if he finds that the information presented is sufficient to determine the project’s compliance with the provisions of this chapter. [Ord. 15-0409 § 1 (Att. A); Ord. 11-0329 § 3 (Exh. 1).]

18.57.060 Tree density requirement.

A. Minimum Tree Density Requirement Established. A minimum tree density is required on each site. The tree density may consist of existing trees, replacement trees, or a combination of existing and replacement trees. The site density of trees to be protected on each site shall be determined prior to approval of a tree protection plan or clearing permit, by the city manager.

B. Tree Density Calculation. The minimum tree density required for each site is 30 tree units per acre of net buildable area.

1. To calculate the density of trees to be protected:

a. Obtain the d.b.h. measurement in inches for each protected tree within the net buildable area.

b. Go to Table 18.57.060A and select the tree unit value that corresponds to the d.b.h. for each protected tree.

c. Add up the tree unit values for all protected trees and divide by the total acreage of the net buildable area. This value must equal or exceed 30 tree units per acre of net buildable area. If the total is less than 30 tree units per acre, more trees must be protected or replacement trees will be required.

d. If replacement trees are planted as groves within designated tracts, then applicant may reduce total tree units required by 10 percent.

 

Table 18.57.060A 
Existing Trees to Remain.

(Conversion from diameter (d.b.h.) in inches to tree units for
trees protected on-site.)

d.b.h.

Tree Units

d.b.h.

Tree Units

1 – 5

1.0

30

8.2

6 – 10

1.2

31

8.6

11

1.4

32

9.0

12

1.8

33

9.5

13

2.0

34

10.0

14

2.3

35

10.5

15

2.6

36

11.0

16

2.9

37

11.5

17

3.2

38

12.0

18

3.5

39

12.5

19

3.8

40

13.0

20

4.2

41

13.5

21

4.6

42

14.0

22

5.0

43

14.5

23

5.4

44

15.0

24

5.8

45

15.5

25

6.2

46

16.0

26

6.6

47

17.0

27

7.0

48

18.0

28

7.4

49

19.0

29

7.8

50

20.0

For every one inch greater than 50 d.b.h., add an additional 2 tree units (i.e., 62 d.b.h. = 44 tree units).

C. Replacement Tree Requirement. If the number of existing trees is not enough to meet the minimum of 30 tree units per acre, a sufficient number of replacement trees shall be planted to meet the minimum requirement. To determine the total number of replacement trees required:

1. Obtain the caliper measurement for each replacement tree. Replacement trees are measured differently than protected trees. Instead of measuring d.b.h. as in protected trees, replacement trees are measured by caliper in inches according to industry standards (ANSI). Caliper on replacement trees is measured six inches above the ground line for four-inch and smaller trees, and 12 inches above ground for larger replacement trees.

2. Go to Table 18.57.060B and select the tree unit value that corresponds to the caliper for each replacement tree.

3. Add the replacement tree unit values together to determine how many of that size tree will be required to achieve the minimum site density. See Table 18.57.060C for an example.

Table 18.57.060B Replacement Trees. 

(Conversion from
caliper inches to tree units for replacement trees.)

Deciduous Tree Caliper in Inches

Tree Units for Deciduous Trees

Coniferous Tree Height in Feet

Tree Units for Conifers

Tree Units for Native Conifers

1.5"

0.4

4' – 6'

0.5

0.8

2"

0.5

6' – 8'

0.7

1.0

3"

0.6

8' – 10'

1.0

1.5

4"

0.7

11' – 12'

1.5

2.0

5"

0.8

 

 

 

6"

1.0

 

 

 

7"

1.2

 

 

 

8" +

1.5

 

 

 

Table 18.57.060C Sample Tree Density Calculation.

The required density factor is calculated below as follows for five acres: five acres x 30 units = 150 tree units required.

Existing density (ED):

Size

Quantity

Total Units

Size

Quantity

Total Units

24"

3

17.4

12"

5

9.0

18"

3

10.5

8"

6

7.2

10"

4

4.8

15"

8

20.8

30"

7

57.4

4"

10

10.0

 

 

 

 

Total ED

137.1

Replacement density (RD):

Size

Units

Quantity

Total Units

2" Deciduous

0.5

12

6.0

4" Deciduous

0.7

6

4.2

4' – 6' Native Conifer

0.8

5

4.0

 

 

Total RD

14.2

ED + RD =

Site Total Tree Density

>

or

=

Minimum Density Required

137.1 + 14.2 =

151.3

>

 

 

150

Density Satisfied

The sum of the ED and RD must be greater than or equal to the minimum density required. [Ord. 11-0329 § 3 (Exh. 1).]

18.57.070 Tree protection plan review procedure.

A. Departmental Review. The city manager shall review the tree protection plan and clearing permit application to determine whether the applicant has provided all required information. Completed applications shall be referred to appropriate City departments for review. Upon request of either the applicant or the City, the City may conduct field inspections or review meetings. City departments involved in the review and/or inspections shall submit their report(s) and recommendation(s) to the city manager.

B. Evaluation for Compliance. The city manager may require an evaluation by a qualified tree protection professional, a qualified engineer, landscape architect, soils engineer, testing lab, or other specialist at any time during the tree protection plan review process or tree removal inspection as necessary to ensure compliance with the provisions of this chapter and/or the terms of the clearing permit. Individual applicants will be responsible for payment to the City of the actual cost to the City of this evaluation. The actual costs of any such evaluation shall be paid to the City within 30 days of receipt of the City’s invoice.

C. Financial Guarantees. For all projects required to have a tree protection plan, financial guarantees shall be required consistent with the provisions of KMC 21.20.070; provided, however, that to the extent that the financial guarantee requirements of KMC 18.57.100 are more protective of tree preservation, performance and maintenance, then the more protective requirements shall prevail. [Ord. 11-0329 § 3 (Exh. 1).]

18.57.080 Tree protection plan review standards.

The following standards shall govern the approval of a tree protection plan and the granting or denial of an application for clearing permit:

A. Design. Development shall be designed, located, and conducted so as to minimize the loss of healthy groves and protected trees as identified by a qualified tree protection professional, degradation of wildlife habitat as identified through environmental review, and the potential for erosion and slope failure.

B. Tree Protection Priority. In designing a development project and in meeting the required minimum tree density, the applicant shall protect trees within the net buildable area as described in KMC 18.57.060(B)(1), in the following order of priority. Trees to be preserved and protected must be healthy and vigorous, wind-firm, and not in conflict with utilities.

1. Groves.

2. Individual trees which provide wildlife habitat as identified through environmental review.

3. Individual trees and groves which occur within required setbacks.

4. Trees that protect against windthrow, including trees sheltering interior trees or trees on adjacent property from strong winds that could otherwise cause them to blow down.

5. Trees which provide a buffer and separate incompatible uses or reduce sound and wind levels.

C. Replacement Tree Planting Conditions. Replacement trees should be planted in areas with soil, climate, exposure, and moisture conditions appropriate to the replacement tree species’ growing requirements as determined by a qualified tree protection professional, licensed landscape architect, or certified nurseryman.

D. Replacement Tree Planting Location Priority. On sites where the number of existing trees falls below the minimum density requirements, then replacement tree planting shall be required. The applicant’s proposed location of transplanted or replacement trees shall be subject to review by a qualified tree protection professional, licensed landscape architect, or certified nurseryman, and City approval as part of the tree protection plan. Replacement trees should be planted according to the following priority:

1. On-Site.

a. Designated Tracts. Trees located in separate deeded tree tracts specifically set aside for the preservation and planting of trees and/or the required recreation open space area if trees do not interfere with recreation activities.

b. Perimeter Landscaping. In which case, replacement trees shall not count toward and shall be in addition to perimeter landscape requirements.

c. Landscaping. This may include entrance landscaping, traffic islands, and other common open space areas. Trees located in a public right-of-way may be credited as replacement trees only if street trees are not a requirement.

2. Off-Site. In cases where an applicant believes that lot size prevents installation of the required number of trees, the applicant may propose to the City payment of a fee in lieu for installation of trees in a public park or other public space. The city manager shall review and make the final decision on the applicant’s proposal, based on a recommendation from a qualified tree protection professional.

E. Replacement Conifer Tree Types. Replacement trees shall be of a similar type of genus to the conifer trees that are removed; i.e., a Western Red Cedar (Thuja plicata) may be replaced with a tree in the genus Thuja, such as an American Arborvitae (Thuja occidentalis). [Ord. 15-0409 § 1 (Att. A); Ord. 11-0329 § 3 (Exh. 1).]

18.57.085 Tree windthrow evaluation and prevention.

A. Increased tree windthrow potential as a result of impacts to trees on a site shall be evaluated based on the following risk factors:

1. Root system disruption that will extend within an area one to two and one-half times the radius of the canopy;

2. Topography of the site;

3. Whether the tree is deciduous or evergreen;

4. Height of the tree relative to the neighboring trees;

5. Whether the tree is part of a grove.

B. The windthrow evaluation shall be conducted as part of the preparation of the tree protection plan (see KMC 18.57.050) based on the aforementioned risk factors. The assessment shall be conducted by a qualified tree protection professional. This assessment also shall evaluate increased windthrow potential for trees on neighboring lots that are within 50 feet of the closest trees being removed on the site, including trees that share a root system with tree(s) on the site.

C. Tree Protection Plan.

1. When significant windthrow potential is identified for trees that could impact neighboring properties or are on neighboring properties, the applicant shall identify measures to minimize windthrow as part of the tree protection plan. Measures could include but are not limited to demonstrating that the critical root zone (CRZ) fencing is adequate to prevent root disruption or that the CRZ is expanded to provide root protection; saving groves when applicable; taking steps to preserve existing grades around trees; and/or tunneling rather than trenching for utilities. The City may deny a request to remove a tree(s) if mitigation measures are inadequate to minimize windthrow.

2. If potential windthrow damage is for the site itself, the applicant shall identify measures to reduce impacts to future structures on the site. [Ord. 15-0409 § 2 (Att. B).]

18.57.090 Tree protection during construction.

Prior to initiating tree removal and any clearing and grading on the site, trees to be protected and preserved shall be protected from potentially damaging activities as follows unless otherwise approved by the City.

A. Critical Root Zone (CRZ). The CRZ of individual trees, groves, or otherwise designated protected tree areas shall include no less than the area of a circle with a radius that extends one foot out from the tree for every inch of trunk d.b.h., or the area of a circle with radius extending from a tree’s trunk to a point no less than the end of a tree’s longest branch, whichever is greater (see Figure 18.57.090A).

B. Tree Protection Fence (TPF). Before development, the applicant:

1. Shall place three inches of composted woodchips over the CRZ of all retained trees to retain moisture, increase organic matter, and visually establish the CRZ.

2. Shall erect and maintain readily visible protective tree fencing a minimum of three feet beyond the outer edge of the CRZ for all individual trees, groves, or other designated protected tree areas.

a. Fencing shall completely surround the required tree protection area. The city manager may allow adjustments to placement of the TPF based on an evaluation of the tree, soils, and proposed disturbance.

b. Fencing shall be a minimum of four feet high and may be higher if needed to ensure clear visual delineation. Chain-link fence or orange plastic fence fastened to steel stakes/posts driven securely into the ground shall be required in order to discourage easy movement.

c. Any deviation from the tree fencing methods listed above must be authorized in writing by the city manager in advance.

3. Shall keep the protective fencing in place until the City authorizes the removal or issues a final certificate of occupancy, whichever occurs first.

4. Shall ensure that any landscaping done within the root protection zone subsequent to the removal of the fence shall not disturb existing trees including roots within the CRZ.

C. Placing Materials Near Tree. During development, no individual, partnership, corporation, association, organization, cooperative, public or municipal corporation, or agency of any governmental unit, however designated, may conduct any activity within the TPF of any tree designated to remain, except as specified in this section.

D. Attachments to Trees. During development, no individual, partnership, corporation, association, organization, cooperative, public or municipal corporation, or agency of any governmental unit, however designated, shall attach any object to any tree designated for protection.

E. Grade.

1. The grade shall not be filled or cut within the CRZ of any tree designated to remain without prior review by a qualified tree protection professional and advance, written approval from the city manager.

2. The applicant shall not install an impervious surface within the protective barrier of any tree designated to remain without the advance, written authorization of the city manager.

3. To the greatest extent practical, utility trenches shall be located outside of the root protection zone of trees to be retained. Boring or tunneling under the CRZ may be considered an alternative, but shall require the advance, written approval of the city manager.

4. Trees and other vegetation to be retained shall be protected from erosion and sedimentation.

F. Additional Requirements. The city manager may require additional tree protection measures which are consistent with accepted urban forestry practices.

Figure 18.57.090A Critical Root Zone.

This section shows a cross-section of the typical root zone for a deciduous tree. Eighty-five percent of the tree’s roots are within the top 18 inches of the soil. Roots typically spread up to two times the height of the tree and sometimes more. However, the critical mass of roots is usually found within the critical root zone. [Ord. 11-0329 § 3 (Exh. 1).]

18.57.100 Post-construction replacement, financial guarantee and maintenance requirements.

A. Replace Damaged, Dead, or Dying Trees. Replacement trees or groves that are damaged or die within a period of three years after planting or transplanting must be replaced in kind at a ratio of one-to-one within six months of the tree’s death or the date of discovery of the damage. Existing trees that are damaged or die within a period of three years after completion of construction activities and as a cause of construction activities as determined by a qualified tree protection professional shall be replaced in kind at a ratio of two-to-one within six months of the tree’s death or date of discovery of the damage.

B. Replacement Tree Quality. Replacement trees shall conform to the American Standards for Nursery Stock, ANSI.

C. Tree Maintenance. All trees shall be maintained in accordance with International Society of Arboriculture guidelines and standards.

D. Financial Guarantee Required. A financial guarantee as defined and regulated under KMC Title 21 shall be required as a mechanism to cover any potential cost associated with replacing dead or dying replacement or existing trees required to satisfy tree unit requirements per this section.

1. A financial guarantee shall be required for all plans requiring 15 or more tree units.

2. Calculation of the amount of the financial guarantee shall be computed based upon equivalent tree replacement value for all replacement and existing trees on the property as determined by a qualified tree protection professional using the most recent edition of the Guide for Plant Appraisal published by the International Society of Arboriculture, in collaboration with the Council of Tree and Landscape Appraisers. Fair market value shall be posted. Fair market value includes the value of the tree(s), installation, and maintenance until establishment that would be required to compensate for the trees that could be lost.

3. The financial guarantee period for maintenance shall be three years, plus an additional 60 days.

4. Release of Financial Guarantee.

a. Upon successful tree replacement and establishment as determined by the written approval of the City and consistent with Chapter 21.15 KMC, the financial guarantee required by this section shall be released.

b. The City, in its discretion, may release a financial guarantee under this section when fee simple title is transferred. The City may condition the release of the existing financial guarantee upon establishment of a new financial guarantee by the new owner in fee simple. [Ord. 11-0329 § 3 (Exh. 1).]

18.57.110 Penalties, enforcement.

A. Civil Penalty. Any violation of any provision of this chapter constitutes a civil violation under Chapter 1.15 KMC, and is subject to the enforcement procedures of Chapter 1.20 KMC; provided, however, that an individual, partnership, corporation, association, organization, cooperative, public or municipal corporation, or agency of any governmental unit, however designated, who removes any tree in violation of this chapter shall be assessed the following civil penalty:

An individual, partnership, corporation, association, organization, cooperative, public or municipal corporation, or agency of any governmental unit, however designated, removing a tree in violation of this chapter shall be assessed a monetary penalty in the amount of $2,000 per inch in diameter at breast height of tree removed. For example, if a 20-inch tree is removed, then the penalty would be $40,000.

B. Criminal Penalty. In addition to or as an alternative to incurring civil liability under this section, an individual, partnership, corporation, association, organization, cooperative, public or municipal corporation, or agency of any governmental unit, however designated, who violates any provisions of this chapter shall be guilty of a misdemeanor and subject to the criminal penalties set forth in Chapter 1.15 KMC, and shall be subject to the procedures of the City’s criminal code, KMC Title 9.

C. Separate Offense. Every individual, partnership, corporation, association, organization, cooperative, public or municipal corporation, or agency of any governmental unit, however designated, violating any provision of this chapter is guilty of a separate offense for each and every day during any portion of which the violation is committed, continued or permitted by any such individual, partnership, corporation, association, organization, cooperative, public or municipal corporation, or agency of any governmental unit, however designated. [Ord. 11-0329 § 3 (Exh. 1).]