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Earlier editions: 2026-09

Title 21 — SUBDIVISIONS›Article II — SUBDIVISION REVIEW PROCEDURES

Diamond Bar Municipal Code Ch. 21.20 Tentative Map Filing and Processing

Diamond Bar Municipal Code · 2026-10 edition · updated 2026-10-04 · Diamond Bar

Cite as: Diamond Bar Municipal Code Chapter 21.20 · Text as of 2026-10-04

Sec. 21.20.010. - Purpose of chapter.

This chapter establishes requirements for the preparation, filing, approval or disapproval of tentative maps, consistent with the requirements of the map act.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.020. - Tentative map preparation; application contents.

Tentative map submittal shall include the application forms, and all information and other materials prepared as required by the department.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.030. - Tentative map filing; initial processing.

(a) General filing and processing requirements. Tentative map applications shall be submitted to the department for processing, be reviewed for completeness and accuracy, referred to affected agencies, reviewed in compliance with the California Environmental Quality Act (CEQA) where applicable, and evaluated in a staff report in compliance with chapter 22.44 (Applications, Processing, and Fees) of the development code.

(b) Property owner list. In addition to the information and materials required for a tentative map application by subsection (a) above, the subdivider shall file a list, certified to be correct by an affidavit or by a statement made under penalty of perjury in compliance with Code of Civil Procedure § 2015.5, of the names and addresses of all persons who are shown on the latest Los Angeles County equalized assessment role as owners of the site proposed for subdivision, and all real property within a distance of 500 feet from the exterior boundaries of the site. The subdivider shall also file a map, in the form required by the department, showing the location of each ownership represented on the list of owners.

(c) Referral to affected agencies. In addition to the procedures outlined in chapter 22.44 (Applications, Processing, and Fees) of the development code, a tentative map application shall be referred to the agencies outlined in this subsection as required by the map act, as well as any other city department, county, state or federal agency, or other individual or group that the director believes may be affected by the subdivision, or may have information useful to the city about issues raised by the proposed subdivision.

(1) Time limits for referrals. As required by map act sections 66453 through 66455.7, referral shall occur within five days of the tentative map application being determined to be complete in compliance with section 22.44.050 (Initial application review - completeness review) of the development code. An agency wishing to respond to a referral shall provide the department with its recommendations within 15 days after receiving the tentative map application.

(2) Required referrals. The director shall refer tentative map applications for review and comment to each of the following agencies, which will be expected to provide service to the proposed subdivision:

a. Caltrans. The California Department of Transportation shall be referred any tentative map located within an area shown on a territorial map filed with the city in compliance with map act section 66455.

b. Fire department. The fire department shall be referred any tentative map, conditional certificate of compliance, or lot line adjustment.

c. Other cities and local agencies. Other cities and other local agencies, shall be referred any tentative map or conditional certificate of compliance application that is located within the area shown on a territorial map filed with the city in compliance with map act section 66453, and within three miles of their official boundaries.

d. Public utilities, water and sewer agencies. Public utility companies and other service agencies which will be expected to provide service to the proposed subdivision, including providers of gas, electrical, telephone, and cable television services, shall be referred any tentative map or conditional certificate of compliance within their respective jurisdictions.

e. Public works department. The public works department shall be referred all tentative maps, conditional certificates of compliance, and lot line adjustments, for review and comment regarding proposed easements, public improvements, streets, and other relevant issues.

f. School districts. Tentative maps shall be referred to the governing board of any elementary, middle school, high school, or unified school district within which the property to be subdivided is located.

g. State department of education. The state department of education shall be notified of any tentative map that includes a proposed public school site.

Along with the subdivision application referral, the department shall include notification that if no written response to the referral is received within 15 calendar days of receipt by the department, the city shall presume that no recommendations or comments are forthcoming.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.040. - Evaluation of application.

After completion of the initial processing and the application being deemed complete in compliance with section 22.44.050 of the development code, the director shall:

(1) Review and evaluate each tentative map as to its compliance and consistency with applicable provisions of this title, the development code, the general plan, any applicable specific plan, and the map act;

(2) Determine the extent to which the proposed subdivision complies with the findings in section 21.20.080 (Tentative map approval or disapproval), and recommend to the commission the approval, approval with specified conditions, or disapproval of the tentative map application; and

(3) Prepare a staff report to the commission in compliance with section 21.20.070 (Tentative map public hearings), describing the conclusions of the director's evaluation, and providing recommendations for commission approval or disapproval of the proposed subdivision.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.050. - Commission review and decision.

After review of a tentative map application by the director, (section 21.20.040, above), the commission shall be responsible for the following:

(1) Hearing and review. The commission shall:

a. Conduct a public hearing on a proposed tentative map, and shall consider the director's recommendations, and any agency providing comments on the tentative map in compliance with section 21.20.030(c) (Tentative map filing, initial processing). The public hearing shall be scheduled and notice provided in compliance with section 21.20.070 (Tentative map public hearings); and

b. Review and evaluate each tentative map as to its compliance and consistency with applicable provisions of this title, the development code, the general plan, any specific plan, and the map act. The commission's evaluation shall be based on the staff report (section 21.20.040), information provided by an initial study or environmental impact report (EIR), where applicable, and any public testimony received.

(2) Recommendations to council. Within 50 days of the tentative map application being deemed complete, the commission shall determine the extent to which the proposed subdivision complies with the findings in section 21.20.080 (Tentative map approval or disapproval), and shall recommend to the council the approval, approval with specified conditions, or disapproval of the tentative map. Any recommended conditions of approval shall comply with section 21.20.090 (Conditions of approval).

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.060. - Council review and decision.

After receiving a recommendation on a tentative map from the commission, the council shall:

(1) Conduct a public hearing on a proposed tentative map in compliance with section 21.20.070 (Tentative map public hearings), and consider the recommendations of the commission and any public testimony; and

(2) Within 30 days after the filing of the report and recommendation of the commission with the council, approve, conditionally approve or disapprove the tentative map.

Approval or conditional approval of a tentative map shall be granted only after the council has first made all findings required by section 21.20.080 (Tentative map approval or disapproval). The council may impose conditions of approval in compliance with section 21.20.090 (Conditions of approval).

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.070. - Tentative map public hearings.

When a public hearing is required by this title for a tentative map, the hearing shall be scheduled and conducted in compliance with this section, in addition to public notice being provided in compliance with chapter 22.72 (Public Hearings) of the development code.

(1) Scheduling of hearing, action. A public hearing on a tentative map shall be scheduled and action shall be taken, within the following time limits. A public hearing on a tentative map shall be scheduled and action shall be taken with 50 days after the tentative map application has been deemed complete. A hearing by the council shall be scheduled within 30 days after the filing of the commission report and recommendation on a tentative map with the council, or within 30 days after the certification of an environmental impact report, adoption of a negative declaration, or a determination by the city that the project is exempt from the requirements of CEQA, whichever is later.

(2) Distribution of staff report. The staff report on the tentative map shall be mailed to the subdivider (and each tenant of the subject property, in the case of a condominium conversion (chapter 21.24)) at least three days before any hearing or action on the tentative map by the commission or council.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.080. - Tentative map approval or disapproval.

In order to approve a tentative map and conditions of approval, or to disapprove a tentative map, the review authority shall first make the findings required by this section. In determining whether to approve a tentative map, the city shall apply only those ordinances, policies, and standards in effect at the date the department determined that the application was complete in compliance with section 21.20.030 (Tentative map filing, initial processing), except where the city has initiated general plan, specific plan or development code changes, and provided public notice as required by map act section 66474.2.

(1) Required findings for approval. The commission may recommend approval, and the council may approve a tentative map, only when it shall first find that the proposed subdivision, together with the provisions for its design and improvement, is consistent with the general plan, and any applicable specific plan, and that none of the findings for disapproval in subsection (3) can be made. The findings shall apply to each proposed parcel as well as the entire subdivision, including any parcel identified as a designated remainder in compliance with map act section 66424.6.

(2) Supplemental findings. In addition to the findings required for approval of a tentative map by subsection (1) above, the review authority shall not approve a tentative map unless it can also make the following findings, when they are applicable to the specific subdivision proposal:

a. Construction of improvements. It is in the interest of the public health and safety, and it is necessary as a prerequisite to the orderly development of the surrounding area, to require the construction of road improvements within a specified time after recordation of the parcel map, where road improvements are required.

b. Condominiums. Any applicable findings required by section 21.24.030 for condominium conversions.

c. Dedications or exactions. Any applicable findings required by section 21.32.030 (Findings required for dedications or exactions), if dedications or exactions are required.

d. Waiver of parcel map. The findings required by section 21.22.030 (Waiver of parcel map), if waiver of a parcel map has been requested with the tentative map application.

(3) Findings requiring disapproval. A tentative map shall be denied if the council makes any of the following findings:

a. The proposed subdivision including design and improvements is not consistent with the general plan or any applicable specific plan;

b. The site is not physically suitable for the type or proposed density of development;

c. The design of the subdivision or the proposed improvements are likely to cause substantial environmental damage or injure fish or wildlife or their habitat;

d. The design of the subdivision or type of improvements is likely to cause serious public health or safety problems;

e. The design of the subdivision or the type of improvements will conflict with easements, acquired by the public at large for access through or use of, property within the proposed subdivision. This finding may not be made if the review authority finds that alternate easements for access or use will be provided, and that they will be substantially equivalent to ones previously acquired by the public. This finding shall apply only to easements of record, or to easements established by judgement of a court of competent jurisdiction, and no authority is hereby granted to the review authority to determine that the public at large has acquired easements of access through or use of property within the proposed subdivision;

f. The discharge of sewage from the proposed subdivision into the community sewer system would result in violation of existing requirements prescribed by the California Regional Water Quality Control Board;

g. A preliminary soils report or geological hazard report indicates adverse soil or geological conditions and the subdivider has failed to provide sufficient information to the satisfaction of the city engineer or council that the conditions can be corrected in the plan for the development; or

h. The proposed subdivision is not consistent with all applicable provisions of this title, the development code, any other applicable provisions of the Municipal Code, and the subdivision map act.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.090. - Conditions of approval.

Along with the approval of a tentative map, the adoption of conditions of approval shall occur in compliance with this section, provided that all conditions shall be consistent with the requirements of the map act.

(1) Mandatory conditions. The review authority shall adopt conditions of approval that will:

a. Require that parcels, easements or rights-of-way be provided for streets, water supply and distribution systems, sewage disposal systems, storm drainage facilities, solid waste disposal and public utilities providing electric, gas and communications services, as may be required to properly serve the subdivision. Easements for public utilities shall be limited to those needed to provide service to present and future development;

b. Mitigate or eliminate environmental problems identified through the environmental review process, except where a statement of overriding consideration has been adopted in compliance with CEQA;

c. Carry out the specific requirements of chapter 21.30 (Subdivision Design and Improvement Requirements) and chapter 21.34 (Improvement Plans and Agreements) of this title;

d. Secure compliance with the requirements of this title and the general plan; and

e. Require that any designated remainder parcels not be subsequently sold or further subdivided unless a certificate or conditional certificate of compliance (chapter 21.28) is obtained in compliance with this title;

f. Require the dedication of additional land for bicycle paths, local transit facilities, (including bus turnouts, benches, shelters, etc.), sunlight easements, and school sites, in compliance with map act chapter 4, article 3, where required by the general plan.

(2) Optional conditions. The review authority may also require as conditions of approval:

a. The waiver of direct access rights to any existing or proposed streets;

b. The reservation of sites for public facilities, including fire stations, libraries, and other public uses in compliance with map act chapter 4, article 4;

c. Time limits or phasing schedules for the completion of conditions of approval, when deemed appropriate; or

d. Any other conditions deemed necessary by the review authority to achieve compatibility between the proposed subdivision, its immediate surroundings, and the community, or to achieve consistency with city ordinances or state law.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.100. - Effective date of tentative map approval.

The approval of a tentative map shall become effective for the purposes of filing a parcel or final map, including compliance with conditions of approval, immediately after the adoption of the resolution of decision by the council.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.110. - Changes to approved tentative map or conditions.

A subdivider may request changes to an approved tentative map or its conditions of approval before recordation of a parcel or final map in compliance with this section. Changes to a parcel or final map after recordation are subject to section 21.22.140 (Amendments to recorded maps).

(1) Limitation on allowed changes. Changes to a tentative map that may be requested by a subdivider in compliance with this section include major adjustments to the location of proposed lot lines and improvements, and reductions in the number of approved lots (but no increase in the number of approved lots), and any changes to the conditions of approval, consistent with the findings required by subsection (4) of this section. The city engineer, except as otherwise provided by this section may approve said changes to a tentative map. Other changes shall require the filing and processing of a new tentative map.

(2) Application for changes. The subdivider shall file an application and filing fee with the department, using the forms furnished by the department, together with the following additional information:

a. A statement identifying the tentative map number, the features of the map or particular conditions to be changed and the changes requested, the reasons why the changes are requested, and any facts that justify the changes; and

b. Any additional information deemed appropriate by the department.

(3) Processing. Proposed changes to a tentative map or conditions of approval shall be processed in the same manner as the original tentative map, except as otherwise provided by this section.

(4) Findings for approval. The review authority shall not modify the approved tentative map or conditions of approval unless it shall first find that the change is necessary because of one or more of the following circumstances, and that all of the applicable findings for approval required by subsections 21.20.080(1) and (2) can still be made:

a. There was a material mistake of fact in the deliberations leading to the original approval;

b. There has been a change of circumstances related to the original approval; and

c. A serious and unforeseen hardship has occurred, not due to any action of the applicant subsequent to the enactment of this title.

(5) Effect of changes on time limits. Approved changes to a tentative map or conditions of approval shall not be considered as approval of a new tentative map, and shall not extend the time limits provided by section 21.20.150 (Expiration of approved tentative map).

(Ord. No. 01(1999), § B, 2-2-99; Ord. No. 02(2000), 4-4-00)

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Sec. 21.20.120. - Completion of subdivision process.

(a) Compliance with conditions; improvement plans. After approval of a tentative map pursuant to this chapter, the subdivider shall proceed to fulfill the conditions of approval within any time limits specified by the conditions and the expiration of the map and, where applicable, shall prepare, file and receive approval of improvement plans pursuant to chapter 21.34 (Improvement Plans and Agreements, Dedications), before constructing any required improvements.

(b) Parcel or final map preparation, filing and recordation.

a. A parcel map for a subdivision of four or fewer parcels shall be prepared, filed, processed and recorded as set forth in chapter 21.22 (Parcel Maps and Final Maps), to complete the subdivision, unless a parcel map has been waived in compliance with section 21.22.030 (Waiver of parcel map).

b. A final map for a subdivision of five or more parcels shall be prepared, filed, processed and recorded as set forth in chapter 21.22 (Parcel Maps and Final Maps), to complete the subdivision.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.130. - Vesting tentative maps.

This section establishes procedures to implement the vesting tentative map requirements of state law, sections 66498.1 et seq. of the map act.

(1) Applicability. Whenever this title requires that a tentative map be filed, a vesting tentative map may instead be filed, provided that the vesting tentative map is prepared, filed and processed in compliance with this section. A vesting tentative map may be filed for either residential, commercial or industrial developments.

(2) Procedures for processing a vesting tentative map. A vesting tentative map shall be filed in the same form, have the same contents and accompanying data and reports and, shall be processed in the same manner as set forth by this chapter as a tentative map, except as follows.

a. Application content. The vesting tentative map shall include the following information in addition to that required by section 21.20.020 (Tentative map preparation, contents):

  1. Title. The vesting tentative map shall be prepared with the words "Vesting Tentative Map" printed conspicuously on its face; and

  2. Intended development. The vesting tentative map application shall include accurately drawn, preliminary floor plans and architectural elevations for all buildings and structures intended to be constructed on the property after subdivision.

b. Findings for approval. The approval of a vesting tentative map shall not be granted unless the review authority first determines that the intended development of the subdivision is consistent with the zoning regulations applicable to the property at the time of filing, in addition to all other findings required for tentative map approval by section 21.20.080 (Tentative map approval or disapproval).

(3) Expiration of vesting tentative map. An approved vesting tentative map shall be subject to the same time limits for expiration as are established for tentative maps by sections 21.20.140 et seq. (Tentative map time limits).

(4) Changes to approved map or conditions. The subdivider may apply for an amendment to the vesting tentative map or conditions of approval at any time before the expiration of the vesting tentative map. An amendment request shall be considered and processed through the same procedures as a new application, in compliance with this section and pursuant to the provisions of the subdivision map act section 66498.2.

(5) Development rights vested.

a. The approval of a vesting tentative map shall confer a vested right to proceed with development of the subdivided lots in substantial compliance with the ordinances, policies and standards (excluding fees) as provided in map act section 66498.1.

b. If map act section 66498.1 is repealed, approval of a vesting tentative map shall confer a vested right to proceed with development in substantial compliance with the ordinances, policies and standards in effect at the time the map is approved or conditionally approved.

c. Subsequent land use permits, building permits, extensions of time or other entitlements filed on parcels created by the subdivision may be conditioned or denied only if the review authority determines that:

  1. A failure to do so would place the residents of the subdivision or the immediate community, or both, in a condition dangerous to their health or safety, or both; or

  2. The condition or denial is required, in order to comply with state or federal law.

d. Fees charged for building or land use permits, filed after the approval of a vesting tentative map shall be as required at the time the subsequent permit applications are filed, including any related utility or development impact fees (e.g., sewer/water hookup fees, traffic mitigation fees, etc.). Application contents shall be as required by ordinance requirements in effect at the time the subsequent application is filed.

(6) Duration of vested rights. The development rights vested by this section shall expire if a parcel map or final map is not approved before the expiration of the vesting tentative map in compliance with sections 21.20.140 et seq. (Tentative map time limits). If the parcel or final map is approved and recorded, the development rights shall be vested for the following periods of time.

a. An initial time period of 24 months from the date of recordation of the parcel or final map. Where several final maps are recorded on various phases of a project covered by a single vesting tentative map, this initial time period shall begin for each phase when the final map for that phase is recorded.

b. The initial 24 months shall be automatically extended by any time used for processing a complete application for a grading permit or for design or architectural review, if processing exceeds 30 days from the date the application is accepted for processing as complete.

c. The subdivider may apply for a one-year extension at any time before the initial 24 months expire. Application for an extension shall be submitted to the department and shall be accompanied by the required fee. The council shall approve or not approve any request for extension.

d. If the subdivider submits a complete application for a building permit during the periods of time specified in subsections (6)a. and (6)b. above, the vested rights shall continue until the expiration of the building permit, or any extension of that permit.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.140. - Expiration of approved tentative map.

The expiration date of a tentative map is determined by map act sections 66452.6, 66452.11, 66452.13, and 66463.5. An approved tentative map is valid for 36 months after its effective date (section 21.20.100). At the end of that time, the approval shall expire and become void unless:

(1) A parcel or final map, and related bonds and improvement agreements, have been filed with the city engineer in compliance with chapter 21.22 (Parcel Maps and Final Maps); or

(2) An extension of time has occurred in compliance with section 21.20.150.

Expiration of an approved tentative map or vesting tentative map shall terminate all proceedings. The application shall not be reactivated unless a new tentative map application is filed.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.150. - Extensions of time for tentative maps.

When a subdivider has not completed all tentative map conditions of approval and filed a parcel or final map with the city within the time limits established by section 21.20.140, time extensions may be granted in compliance with this section. Extension requests shall be in writing and shall be filed with the department on or before the date of expiration of the approval or previous extension, together with the required filing fee.

(1) Tentative maps. The council may grant extensions to the initial time limit up to a maximum total of three years, only after finding that:

a. There have been no changes to the provisions of the general plan, any applicable specific plan, this title, or the development code applicable to the project since the approval of the tentative map;

b. There have been no changes in the character of the site or its surroundings that affect how the policies of the general plan or other standards of this title or the development code apply to the project; and

c. There have been no changes to the capacities of community resources, including but not limited to water supply, sewage treatment or disposal facilities, roads or schools so that there is no longer sufficient remaining capacity to serve the project.

(2) Tentative maps with multiple final maps. Where a subdivider is required to expend more than $125,000.00 on improvements as specified in map act section 66452.6 and multiple final maps are filed covering portions of a single approved tentative map, each filing of a final map shall extend the expiration of the tentative map by an additional 36 months from the date of its expiration, or the date of the previously filed final map, whichever is later. The total of all extensions shall not extend the approval of the tentative map more than ten years from its approval.

(3) Vesting tentative maps. The council may grant extensions for a maximum total of three years to the initial time limit in compliance with subsection (1) of this section.

(Ord. No. 01(1999), § B, 2-2-99)

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Sec. 21.20.160. - Applications deemed approved.

Any subdivision application deemed approved in compliance with Government Code § 65956, or map act § 66452 et seq., shall be subject to all applicable provisions of the development code (title 22 of the Municipal Code), which shall be satisfied by the subdivider before any building permits or other land use entitlements are issued. Parcel or final map filed for record after the automatic approval of their tentative map shall remain subject to all the mandatory requirements of the development code and the map act, including, but not limited to map act §§ 66473, 66473.5 and 66474.

(Ord. No. 01(1999), § B, 2-2-99)

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