12.30.070 Permissive modifications in regulations – Clustered subdivisions and attached residential PUDs.
Clustered subdivision and attached residential PUDs shall be subject to the following limitations in modification of regulations in addition to the applicable limitations set forth in BMC 12.30.030, 12.30.040 and 12.30.050:
A. For clustered subdivision PUDs, the minimum lot area as required in Chapter 12.14 BMC within the R 5,400d, R 7,200, R 8,400 and R 9,600 zoning classifications may be reduced up to 50 percent.
B. For clustered subdivision PUDs, the minimum lot area as required in Chapter 12.14 BMC within the R 40,000 zoning classification may be reduced up to 60 percent.
C. For clustered subdivision PUDs, the minimum lot circle diameter as required in Chapter 12.14 BMC within the R 5,400d, R 7,200, R 8,400 and R 9,600 zoning classifications may be reduced up to 50 percent.
D. For clustered subdivision PUDs the minimum lot circle diameter as required in Chapter 12.14 BMC within the R 40,000 zoning classification may be reduced up to 60 percent.
E. The number of lots in a clustered subdivision PUD shall be subject to the following lot yield methodology:
1. The net buildable area of the development site shall be determined pursuant to BMC 12.14.030(B)(3) wherein land area in roads and other rights-of-way, critical areas, critical area buffers, or land dedicated to the city for other purposes shall be deducted from the gross site area;
2. To determine the number of allowed lots upon the subject property, the net buildable area shall be divided by the underlying zoning classification’s minimum lot area thereby deriving the number of allowed lots using whole numbers only. Rounding up is not permitted;
3. Portions of the net buildable area placed into a dedicated open space tract pursuant to subsection J of this section shall be credited toward the allowed lot yield calculation; and
4. An increase in the number of allowed lots for clustered subdivisions PUDs shall be permitted consistent with subsection (K)(1)(c) of this section.
F. For attached residential PUDs, the number of dwelling units within the R 2,800, R 4,000 and R 5,400a zones shall be subject to BMC 12.14.030(B)(3) and the following:
1. Portions of the net buildable area placed into a dedicated open space tract pursuant to subsection K of this section shall be credited toward the allowed unit yield calculation; and
2. An increase in the number of allowed dwelling units for attached residential PUDs shall be permitted consistent with subsection (K)(1)(d) of this section.
G. Side and Rear Yard Setbacks. Side and rear yard setbacks may be modified consistent with BMC 12.30.030(B).
H. Front Yard Setbacks. Front yard setbacks for individual lots may be modified consistent with BMC 12.30.040(D).
I. Building Coverage. The maximum building coverage percentage within the R 9,600, R 8,400, R 7,200 and R 5,400d zoning classifications for each residential lot within a clustered subdivision PUD may be increased up to 45 percent of the lot area; provided, however, that the total building coverage allowed on the total development site shall be no greater than 35 percent of the net buildable area of the development site.
J. Hard Surface Cover. The maximum hard surface cover for each residential lot within a clustered subdivision PUD may be increased consistent with the schedule below; provided, however, that the maximum amount of hard surface coverage shall be no greater than that established for the underlying zoning classification as applied to the net buildable area of the development site:
1. R 40,000 Zone. No increase in hard surface coverage is allowed;
2. R 9,600 Zone. Hard surface coverage placed within individual lots may increase from 45 percent up to a maximum of 55 percent;
3. R 8,400 Zone. Hard surface coverage placed within individual lots may increase from 50 percent up to a maximum of 60 percent;
4. R 7,200 Zone. Hard surface coverage placed within individual lots may increase from 65 percent up to a maximum of 75 percent; and
5. R 5,400d Zone. Hard surface coverage placed within individual lots may increase from 70 percent up to a maximum of 80 percent.
K. Open Space Preservation. Clustered subdivision and attached residential PUDs shall reserve a portion of the site as dedicated, permanent open space not available for future development consistent with the following criteria:
1. Amount and Minimum Dimension of Land to Be Preserved.
a. All clustered subdivision PUDs shall provide for a minimum of 10 percent of the net buildable area of the site to be placed within a dedicated tract or tracts containing intact forest, rehabilitated or restored forest, a forest equivalent surface water facility, as defined herein, a tree preservation, or another type of passive open space tract to be preserved in perpetuity consistent with the provisions of subsection (K)(3) of this section;
b. Land preserved under this section shall meet the following dimensional standards:
(1) All open space tracts for clustered subdivision PUDs shall provide an average horizontal dimension equal to 50 percent of the underlying zoning minimum lot circle diameter with a minimum horizontal dimension of 20 feet;
(2) All open space tracts for clustered subdivision PUDs shall cover an area that is at least 50 percent of the minimum lot area of the underlying zoning classification;
(3) All open space tracts for attached residential PUDs shall provide an average horizontal dimension of at least 25 feet with a minimum dimension of 15 feet; and
(4) All open space tracts for attached residential PUDs shall cover an area that is at least equal to the underlying zoning classification minimum land area per dwelling unit;
c. For clustered subdivision PUDs, the city may approve an increase in the number of lots beyond the number established by the allowed lot yield method of subsection E of this section provided additional land is placed within a dedicated tract containing intact forest, rehabilitated or restored forest, forest equivalent surface water facility as defined herein, a tree preservation, or other type of passive open space, which tract is to be preserved in perpetuity consistent with the provisions of subsections (K)(2) and (K)(3) of this section, consistent with the following schedule:
(1) Preserving at least 15 percent of the net buildable area as open space tract consistent with this section, an increase of 10 percent of the calculated lot yield; or
(2) Preserving at least 20 percent of the net buildable area within an open space tract consistent with this chapter, an increase of 15 percent of the calculated lot yield; or
(3) Preserving at least 25 percent of the net buildable area with an open space tract consistent with this chapter, an increase of 20 percent of the calculated lot yield; or
(4) Preserving at least 30 percent of the net buildable area within an open space tract consistent with this chapter, an increase of 25 percent of the calculated lot yield;
d. For attached residential PUDs, the city may approve an increase in the number of dwelling units beyond the number established by BMC 12.14.030(B)(3) provided additional land, not including recreation area as required under Chapter 12.20 BMC, is placed within a dedicated tract consistent with subsections (K)(2) and (K)(3) of this section, and the following schedule:
(1) Preserving at least 20 percent of the net buildable area within an open space tract consistent with this chapter, an increase of 10 percent of the calculated dwelling unit yield; or
(2) Preserving at least 25 percent of the net buildable area within an open space tract consistent with this chapter, an increase of 15 percent of the calculated dwelling unit yield; or
(3) Preserving at least 30 percent of the net buildable area with an open space tract consistent with this chapter, an increase of 20 percent of the calculated dwelling unit yield; or
(4) Preserving at least 40 percent of the net buildable area within an open space tract consistent with this chapter, an increase of 25 percent of the calculated dwelling unit yield.
2. Type of Land to Be Preserved as Open Space. The type of open space shall be based upon the following hierarchical preferences. Applicants shall demonstrate that all reasonable efforts have been made to design the development in a manner that preserves the types of lands listed herein consistent with these hierarchical priorities:
a. Intact forest areas as defined within Chapter 11.02 BMC;
b. Rehabilitated or restored forest areas as defined within Chapter 11.02 BMC;
c. Lands containing existing trees preserved pursuant to Chapter 12.18 BMC;
d. Lands adjacent to critical area buffers which are also enhanced pursuant to Chapter 14.04 BMC;
e. Lands used for forest equivalent surface water facilities, provided such facilities shall be limited to bio-infiltration or surface water dispersion into forest lands;
f. Lands used for passive recreational open space purposes may contain trails, picnic tables, benches, and open lawn areas; provided, that existing significant trees shall not be removed to create open lawn areas and/or other passive recreational uses. Up to 20 percent of the passive recreational open space area may be used for active recreation uses such as playgrounds, tot lots, sports courts, playfields, shelters, gazebos, and other active recreation open space uses.
All passive and active recreational open space areas shall be accessible to residents of the development via dedicated access tracts or easements that are at least 10 feet in width; and
g. Lands used for passive open space purposes containing trails, picnic tables, benches, and other passive recreational uses, provided such areas are accessible to residents of the development via access tracts or easements that are at least 10 feet in width.
3. All lands preserved as open space shall be placed into a separate and permanent open space tract as follows:
a. All open space tracts shall be recorded on all documents of title of record for all affected lots.
b. Open space tracts shall be designated on the face of the plat or recorded drawing in a form as approved by the city attorney and shall be placed within an individual tract. The designation shall include the following restrictions:
(1) The stated purpose of the open space tract shall be clearly indicated. For example, if the open space tract is adjacent to a critical area, the tract shall stipulate the purpose is to prevent harm to the environment, including, but not limited to, controlling surface water runoff and erosion, buffering, protecting plants, fish, and animal habitat, etc. If the purpose is to preserve existing mature trees and other plant materials, the tract shall stipulate that trees may not be removed except as needed to protect the health, safety and welfare of adjacent residential structures as reviewed and authorized by the city of Bothell; and
(2) The right of the city to enforce the terms of the restriction.
c. The city may require that the open space tract be held for its stated purpose in an undivided interest by each owner of a building lot within the development with the ownership interest passing with the ownership of the lot, or held by an incorporated homeowners’ association or other legal entity (such as a land trust or authorized entity, which ensures the ownership, maintenance, and protection of the tract).
d. Statements shall be included which provide that the open space tract shall not be subject to future development or alteration except for maintenance of the tract for its intended purpose or for other common activities associated with the purpose of the tract.
L. Clustered subdivision PUDs within the R 40,000, R 9,600, R 8,400, R 7,200, and R 5,400d zones may allow attached residential developments such as townhouses or other types of attached residential development, provided the dwelling unit is contained within its own individual lot, subject to the following additional requirements:
1. At least 40 percent of the net buildable area is preserved within a permanent open space tract as described in subsections (K)(2) and (K)(3) of this section;
2. All buildings containing three or more dwelling units shall be set back from the perimeter of the development as described within BMC 12.30.030(A) a minimum of 30 feet and shall install a Type III landscape buffer. Should the development contain both attached and detached residential buildings, the portion of the site that contains detached residential buildings may apply the 20-foot perimeter setback dimension of BMC 12.30.030(A);
3. Attached residential buildings shall comply with the requirements of BMC 12.14.200, Exterior building design – Multiple-family residential; and
4. Increases in the lot yield for attached residential dwelling units as established under subsection K of this section shall be limited to a maximum of a 20 percent increase in lot or dwelling unit yield.
M. Clustered subdivision and attached residential PUDs are eligible for modifications to the Bothell Design and Construction Standards and Specifications as adopted in BMC 17.02.010 in accordance with the same modifications available for a green PUD as described within BMC 12.30.060(G). (Ord. 2282 § 8, 2019; Ord. 2221 § 2 (Exh. B), 2017).