Agenda 04/11/2017 Item # 9B04/11/2017
EXECUTIVE SUMMARY
Recommendation to consider an Ordinance amending Ordinance Number 04-41, as amended, the
Collier County Land Development Code, which includes the comprehensive land regulations for the
unincorporated area of Collier County, Florida, by providing for: Section One, Recitals; Section
Two, Findings of Fact; Section Three, Adoption of Amendments to the Land Development Code,
more specifically amending the following: Chapter Six - Infrastructure Improvements and
Adequate Public Facilities Requirements, including Section 6.05.01 Water Management
Requirements, adding Section 6.05.03 Stormwater Plans for Single-Family Dwelling Units, Two-
Family Dwelling Units, and Duplexes; Section Four, Conflict and Severability; Section Five,
Inclusion in the Collier County Land Development Code; and Section Six, Effective Date. (This is a
companion to Agenda Item 16.A.8).
OBJECTIVE: To obtain the Board of County Commissioners (Board) approval of the proposed 2016
Land Development Code (LDC) Amendments Cycle 1, relating to stormwater plans, in order to serve the
best interest of the public.
CONSIDERATIONS: The 2016 Land Development Code Amendment Cycle 1 amendments were
reviewed at the March 14, 2017 Board of County Commissioners meeting, and again at the March 28,
2017 meeting. All of the amendments, except the amendment relating to stormwater plans (as described
below), were approved by the Board on March 28, 2017. The amendment relating to stormwater plans for
specific residential uses was continued to the April 11, 2017, meeting to allow for additional vetting with
stakeholders. This amendment is described in more detail below:
Stormwater Plan Amendment - LDC section 6.05.01 Water Management Requirements
This section establishes maximum lot coverage and impervious areas to address impacts associated with
stormwater runoff flowing onto neighboring properties. However, staff has found that the current
standards do not adequately protect against the possibility for stormwater impacts. Moreover, in 2013, the
Development Services Advisory Committee reviewed the stormwater plan requirements in this section
and determined that the maximum lot coverage and impervious areas are disproportionately limiting on
Estates lots and recommended an LDC amendment reevaluate the lot coverage and impervious area
thresholds.
This amendment removes the maximum lot coverage, establishes two types of stormwater plans, and
expands the requirement for a stormwater plan to all new buildings, additions, or redevelopment of
single-family dwellings, two-family dwellings, and duplexes (with some exceptions). Type I stormwater
plans, require applicants demonstrate where stormwater is intended to flow, while Type II stormwater
plans require an engineered plan similar to those required by the current code. Furthermore, the
impervious area thresholds for engineered plans have been modified to reduce the number of lots required
to provide an engineered plan.
Administrative Code for Land Development Section
A new section related to stormwater plans is proposed to be added to Administrative Code for Land
Development to identify application requirements relating to the LDC amendment. This new section is
included as an exhibit this LDC amendment for informational purposes.
COLLIER COUNTY PLANNING COMMISSION RECOMMENDATION: The Planning
Commission reviewed the LDC amendments on December 15, 2016, January 5, 2017, January 19, 2017,
and January 30, 2017. The Planning Commission unanimously approved the LDC amendments during a
special nighttime hearing on January 30, 2017.
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04/11/2017
FISCAL IMPACT: There are no fiscal impacts associated with this Executive Summary.
LEGAL CONSIDERATIONS: This item has been approved as to form and legality and requires an
affirmative vote of four for Board approval. - SAS
GROWTH MANAGEMENT IMPACT: As noted for each individual amendment.
RECOMMENDATION: That the Board approve the attached proposed ordinance relating to stormwater
plans for single-family dwellings, two-family dwellings, and duplexes for the 2016 Land Development
Code Amendments Cycle 1 and direct staff as to any changes.
Prepared By: Caroline Cilek, AICP, CFM, Land Development Code Manager, Development Review
Division
ATTACHMENT(S)
1. LDC section 6.05.01 Water Management Requirements (PDF)
2. Administrative Code for Land Development Chapter 4.M (PDF)
3. 2016-1 Draft ordinance - stormwater- 3.29.17 (PDF)
4. Legal Ad (PDF)
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04/11/2017
COLLIER COUNTY
Board of County Commissioners
Item Number: 9.B
Doc ID: 2957
Item Summary: ***This item has been continued from the March 28, 2017, BCC meeting***
Recommendation to consider an Ordinance amending Ordinance Number 04-41, as amended, the Collier
County Land Development Code, which includes the comprehensive land regulations for the
unincorporated area of Collier County, Florida, by providing for: Section One, Recitals; Section Two,
Findings of Fact; Section Three, Adoption of Amendments to the Land Development Code, more
specifically amending the following: Chapter Six - Infrastructure Improvements and Adequate Public
Facilities Requirements, including Section 6.05.01 Water Management Requirements, adding Section
6.05.03 Stormwater Plans for Single-Family Dwelling Units, Two-Family Dwelling Units, and Duplexes;
Section Four, Conflict and Severability; Section Five, Inclusion in the Collier County Land Development
Code; and Section Six, Effective Date. (This is a companion to Agenda Item 16.A.8).
Meeting Date: 04/11/2017
Prepared by:
Title: Planner, Senior – Growth Management Development Review
Name: Jeremy Frantz
03/27/2017 2:01 PM
Submitted by:
Title: Project Manager, Principal – Growth Management Department
Name: Matthew McLean
03/27/2017 2:01 PM
Approved By:
Review:
Growth Management Department Judy Puig Level 1 Division Reviewer Completed 03/27/2017 2:04 PM
Zoning Michael Bosi Additional Reviewer Completed 03/27/2017 2:13 PM
Growth Management Development Review Caroline Cilek Additional Reviewer Completed 03/27/2017 2:26 PM
Growth Management Department Judy Puig Level 2 Division Administrator Skipped 03/27/2017 2:20 PM
Growth Management Department James French Additional Reviewer Completed 03/27/2017 5:00 PM
County Attorney's Office Scott Stone Level 2 Attorney Review Completed 03/29/2017 4:45 PM
Office of Management and Budget Valerie Fleming Level 3 OMB Gatekeeper Review Completed 03/29/2017 4:54 PM
County Attorney's Office Jeffrey A. Klatzkow Level 3 County Attorney's Office Review Completed 03/30/2017 10:29 AM
Budget and Management Office Mark Isackson Additional Reviewer Completed 03/30/2017 12:02 PM
County Manager's Office Nick Casalanguida Level 4 County Manager Review Completed 04/03/2017 6:48 AM
Board of County Commissioners MaryJo Brock Meeting Pending 04/11/2017 9:00 AM
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LDC Amendment Request
ORIGIN: Growth Management Department
AUTHOR: Growth Management Department Staff
DEPARTMENT: Growth Management
AMENDMENT CYCLE: 2016 LDC Amendment Cycle
LDC SECTION(S): 6.05.01 Water Management Requirements
6.05.03 Stormwater Plans for Single-Family Dwelling Units, Two-Family
Dwelling Units, and Duplexes (new section)
CHANGES: This amendment expands the requirement for a stormwater plan for all new
buildings, additions, or redevelopment of single-family dwellings, two-family dwellings, and
duplexes. Currently, only those lots that exceed the maximum lot coverage or impervious area are
required to submit a stormwater plan. This amendment removes the maximum lot coverage,
requires a stormwater plan on all lots and increases the impervious area thresholds for when an
engineered plan is required. Exceptions to the requirement for stormwater plans are provided for
lots in the Rural Agricultural (A) zoning district that are outside the coastal urban area and
Immokalee urban area, and for lots within a project that has been permitted by the South Florida
Water Management District (SFWMD) for Surface Water Management or Environmental
Resource Protection.
The amendment establishes two types of stormwater plans as described in Tables 1 and 2 below:
Table 1. Type I Stormwater Plans.
Required for: Type I Stormwater Plans shall demonstrate:
Lots with 40 percent or less
impervious area.
1. The direction of stormwater discharges.
2. Compliance with design standards for
retaining walls, French drains, stormwater
pipes, gutters and downspouts.
3. The location, dimension, and setbacks of
septic systems, if applicable.
Lots in the Estates district with 25
percent or less impervious area.
Lots in RSF-1 or Rural Agricultural
(A) districts in the urban area with 30
percent or less impervious area.
Lots that discharge directly into a
waterbody that is downstream of the
last control structure (regardless of
impervious area).
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Table 2. Type II Stormwater Plans.
Required for: Type II Stormwater Plans shall
demonstrate:
Lots with more than 40 percent
impervious area.
1. Compliance with all Type I Stormwater
Plan criteria.
2. Water quantity calculations to
accommodate the runoff from the area
exceeding the Type II Stormwater Plan
thresholds from a 5-year 1-day storm.
3. A matrix of all required separation
distances between wells, drainfield
systems, and stormwater
retention/detention areas.
4. Certification of compliance by the
engineer.
Lots in the Estates district with more
than 25 percent impervious area.
Lots in RSF-1 or Rural Agricultural
(A) districts in the urban area with
more than 30 percent impervious
area.
Lots that discharge directly into a
waterbody that is upstream of the last
control structure (regardless of
impervious area).
Additionally, the amendment establishes Type I and Type II Stormwater Plans as the tool for
demonstrating compliance with Collier County Code of Laws and Ordinances section 90-41 (f)(8).
A new application process for stormwater plans is also established in the Administrative Code.
REASON:
History
The current standards in LDC section 6.05.01 F were created in 2007 to address impacts associated
with large homes on small lots in conventional zoning districts. At that time, it was determined
that lots exempt from obtaining a SFWMD permit were designed to accommodate a typical amount
of lot coverage or impervious area. Therefore, it was determined that when a large home exceeds
the typical lot coverage or impervious area for that neighborhood, the home may result in impacts
to neighboring properties or the local stormwater system. As a result, a requirement to provide a
stormwater plan was established to address stormwater runoff from lots with a greater than average
percentage of lot coverage or impervious area.
In 2013, the Development Services Advisory Committee (DSAC) reviewed the stormwater plan
requirements in this section. At that time, they identified that the maximum lot coverage and
impervious areas are disproportionately limiting on Estates lots and recommended that an LDC
amendment address the lot coverage and impervious area thresholds. The amendment was then
added to the prioritized list of LDC amendments and approved by the Board of County
Commissioners. Following DSAC’s discussion of these standards, staff conducted additional
research and found several other areas for improvement in the current program as described in the
following sections.
Staff Research
Staff analyzed data from lot coverage reviews that occurred during a one-year period from June
2015 to June 2016. Staff members who regularly perform lot coverage reviews also identified
common problems with stormwater plan submittals and the current standards. As a result, staff has
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proposed changes to address not only disparities in the current thresholds, but also to resolve
several issues related to other elements of stormwater plans:
Thresholds
Analysis of the current thresholds confirmed that the maximum lot coverage and maximum
impervious area percentages do not apply consistently as lot sizes increase. Additionally, this
analysis has demonstrated that the percentage of lot coverage/impervious area allowed is
inconsistent once lot sizes exceed 53,000 square feet. Figure 1 demonstrates how the allowed lot
coverage and impervious areas change as lot sizes increase. For small lots, the maximum allowed
lot coverage begins at 25 percent and the maximum allowed impervious area begins at 40 percent.
However, larger lots are limited to a maximum lot coverage and impervious area of less than 5
percent.
Figure 1. Percent of Allowed Lot Coverage and Impervious Area at Varying Lot Sizes.
Common problems
LDC section 6.05.01 F is intended to address impacts associated with stormwater runoff flowing
onto neighboring properties. However, the current standards do not adequately protect against the
possibility for stormwater impacts. For properties that do not exceed the existing thresholds, no
review is performed when improvements are made to the property to ensure stormwater does not
flow to neighboring properties. However, even lots with a low percentage of lot coverage and
impervious area have the potential to impact their neighbors through site grading changes, slopes
or new structures near the property line, and other site features.
For lots that exceed the existing lot coverage or impervious area thresholds, while retention or
detention of stormwater is required, the current standards still do not adequately protect against
the possibility for stormwater impacts. There are no criteria related to berms or slopes near the
impacted area and there is no requirement for runoff to physically connect to the retention area.
This means that although a retention area may be provided, there is no guarantee that the retention
captures any of the runoff from impervious areas on site or that other site features won’t result in
a change in flow patterns and create stormwater impacts on neighboring properties.
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Moreover, there are some types of impervious surfaces that are not required to obtain a permit and
therefore may not be counted toward the maximum impervious area. However, any impervious
surfaces still have the potential to change stormwater runoff patterns.
Exemptions
Several exemptions are provided in the current standards. One of these allows an additional 3
percent (up to a maximum of 1,000 square feet) lot coverage or impervious area for first time
additions only. However, this additional lot coverage is not exempt during subsequent additions.
This means that if a stormwater plan is required for future additions, retention will then be required
for the area that was previously exempt from the standards.
Another exemption applied to lot coverage and impervious area reviews is for additions less than
400 square feet. Additions less than 400 square feet are not reviewed, even when the maximum lot
coverage or impervious area has already been exceeded. The nexus for both of these exemptions
is not clear and they could allow for stormwater impacts to occur, therefore, there are no size
exemptions in the proposed amendment.
Approval process
Lot coverage and impervious area calculations are currently only required when on site retention
is required. As a result, property owners submitting a building permit may not be aware how much
impervious area is on their lot until they have exceeded the thresholds. This can make thoughtful
planning of the lot difficult for property owners. This difficulty is compounded when separate
permits for a home and pool are submitted simultaneously. In some cases, one permit may indicate
a stormwater plan is required, while the other does not. This can be confusing for property owners
and again makes planning the development of the lot unpredictable. With this in mind, staff
believes the current process does not effectively communicate stormwater plan requirements to
property owners. For these reasons, the proposed amendment more clearly defines when
stormwater plans are required, how they should be prepared, and other procedural considerations.
The new Administrative Code section proposed in Appendix A is also intended to more clearly
define the approval process for stormwater plans.
Other communities
Staff reviewed lot coverage and stormwater management requirements for single-family
dwellings, two-family dwellings, and duplexes in 15 other communities and municipalities
throughout Florida. Three characteristics of stormwater management were common in other
communities:
1. Maximum lot coverage percentages and stormwater management applicability is based on
zoning districts, rather than lot sizes, in nearly all communities reviewed.
2. When stormwater management is required, standards are established for all lots, rather than
just those exceeding the maximum percentage of lot coverage or impervious area.
3. Other communities do not allow lots to exceed lot coverage or impervious area maximums.
As a result of this review of stormwater management in other communities, it is proposed that the
thresholds that require a stormwater plan now apply differently to several zoning districts. This
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change reflects differences in land use and development trends in each district. Additionally, due
to this review and other staff findings described above, it is proposed that stormwater plans are
required for all lots, with some exceptions.
Proposed Standards
Over the course of six Development Services Advisory Committee-Land Development Review
(DSAC-LDR) Subcommittee meetings in 2016, staff collaborated with subcommittee members
and stakeholders to review the current standards, identify goals for the amendment, and develop
the standards included in this amendment. The following sections describe the changes proposed
in this amendment.
Goals of the current amendment
Based on DSAC’s 2013 input and the findings in the additional research outlined above, staff
identified several goals for the current amendment:
Eliminate the inequity of the current applicability thresholds.
Provide better justification for the standards.
Provide stormwater management for runoff on all lots.
Create a program that is more predictable for property owners and increase communication
between reviewers and applicants.
These goals are aimed at preventing detrimental impacts both on site and on adjacent properties
and will apply stormwater management standards more fairly throughout the entire county.
Applicability
This amendment maintains the current applicability to all lots with single -family and two-family
dwellings, and duplexes. The current exemption for lots with a permit from the SFWMD for
surface water management or environment resource protection is maintained, however, an
exemption is added for non-urban agriculturally zoned lots.
Stormwater plans are currently only required when the lot coverage or impervious area exceeds
the thresholds in Table 6.05.01 F. This amendment removes Table 6.05.01 F and adds a
requirement for one of two types of stormwater plans for all lots, based only on impervious area
thresholds specific to each zoning district. The characteristics of each stormwater plan are
described in more detail in Tables 1 and 2 above, and the following sections.
This change is made in response to staff’s experience that drainage issues are not only associated
with a high percentage of impervious area. Staff has found that due to updated building
requirements, new construction is required to use more fill to build to a higher flood elevation than
in the past. In these cases, the fill pad, slopes, and other site grading can have an impact on a
neighborhood’s drainage patterns even when the total impervious area is low. Therefore, a
stormwater plan is necessary on all lots to ensure that drainage from new homes or additions does
not create detrimental impacts on the subject property or adjacent properties. However, the
requirements for stormwater plans for lots with low impervious area is designed to be less onerous
than for lots with high impervious area. Therefore, a Type I Stormwater Plan is established for lots
with relatively lower impervious areas and a Type II Stormwater Plan is established for properties
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with high impervious areas to ensure stormwater runoff does not result in detrimental impacts on
site or to adjacent properties.
Plan submittal
Property owners will continue to submit stormwater plans concurrently with a building permit,
consistent with the current submittal requirements. The stormwater plan submittal process is also
described in more detail in the proposed Administrative Code section in Appendix A.
Stormwater plan thresholds
The proposed amendment uses impervious area thresholds to determine whether a Type I or Type
II Stormwater Plan is required. In urban areas, where lot sizes are typically small, the DSAC-LDR
Subcommittee found that the current threshold for lots under 11,000 square feet is appropriate for
the urban area and, based on staff’s research, ensures that a majority of property owners in the
urban area will not exceed the threshold. As a result, a Type I Stormwater Plan is required for lots
with 40 percent or less impervious area and a Type II Stormwater Plan is required for lots with
more than 40 percent impervious area.
On lots in Estates zoning districts, where the DSAC-LDR Subcommittee found that the current
impervious area thresholds are disproportionately limiting, a Type I Stormwater Plan is required
for lots with 25 percent or less impervious area and a Type II Stormwater Plan is required for lots
with more than 25 percent impervious area. Currently many lots in the Estates are required to
provide a stormwater plan with lot coverage and impervious areas of less than 10 percent. The
DSAC-LDR Subcommittee reviewed staff’s research and aerials of existing sites in the Estates
and determined that lots with 25 percent or less impervious area represent appropriate impervious
areas for Estates lots and should not require stormwater calculations.
On lots in RSF-1 zoning districts and Rural Agricultural (A) zoning in the urban areas, a Type I
Stormwater Plan is required for lots with 30 percent or less impervious area and a Type II
Stormwater Plan is required for lots with more than 30 percent impervious area. This threshold
reflects that RSF-1 lots and Rural Agricultural (A) zoned lots in the urban areas are frequently
larger than other typical urban lots and sometimes have unique infrastructure constraints.
Finally, lots that discharge directly into a waterbody downstream of the last control structure may
submit a Type I Stormwater Plan regardless of the impervious area on the lot. These waterbodies
are uncontrolled and tidally affected, therefore, discharges will not result in stormwater runoff
impacts to neighboring properties. However, for lots discharging directly into a controlled
waterbody, upstream of the last control structure, a Type II Stormwater Plan must be submitted,
regardless of the impervious area on the lot. These discharges have the potential to impact
neighboring properties or the stormwater system and require some retention or detention before
discharging into the waterbody.
Criteria for Type I Stormwater Plans:
Lots required to submit a Type I Stormwater Plan have a comparatively lower percentage of
impervious area. As a result, Type I Stormwater Plans are the least complex type of stormwater
plan. These plans are required to demonstrate that stormwater will be directed to appropriate
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locations without impacting neighboring properties. While on-site retention may be provided on
lots with a Type I Stormwater Plan, no on-site retention is required.
The Type I Stormwater Plan criteria allow for a wide range of methods to address stormwater. On
some sites, the stormwater plan may require more drainage infrastructure to direct stormwater to
appropriate locations, while other sites may simply require grading of the site to meet the
stormwater plan criteria. As a result, the amendment allows either a Florida registered design
professional (such as architects, landscape architects, or engineers), a certified contractor, or owner
builder to design the stormwater plan.
Type I Stormwater Plans are required to demonstrate:
The direction of stormwater discharges. This criterion ensures that stormwater runoff
is directed away from neighbors and allows stormwater runoff to discharge to one or
more of the following:
o An existing surface water management system.-
o A drainage conveyance system, such as swales or underground storm sewer
systems.
o On-site retention or detention areas.
o A waterbody downstream of the last control structure.
Outfalls to a waterbody must also demonstrate that they will not result in
erosion of soil, and if an orifice is used, will be allowed through a
minimum 3-inch orifice. Also, the soil adjacent to the discharge area shall
be stabilized.
Compliance with several design standards.
o Retaining wall setbacks. To allow for maintenance of retaining walls, a six-inch
setback from the property line is required.
o Retention calculations for French drains. When French drains are used, a 40
percent void ratio shall be used in retention calculations.
o Stormwater pipe specifications. If used, stormwater pipes shall not be metal.
This standard is intended to prevent pipe installations with relatively short life
spans.
o Gutter and downspout standards in 6.05.01 C. This requirement ensures that
downspouts are not pointed toward neighboring properties when a structure is
located 10 feet or less from a property line. It should be noted additional
requirements for downspouts can be found in Florida Statutes Chapter
381.0065(4)(s), which also requires that downspouts are directed away from the
septic system drainfield, if one is located on the property.
The location, dimension, and setbacks of septic systems. If a septic system is present or
proposed on the property, this criteria ensures that the design and location of stormwater
management and septic systems is coordinated throughout the development of the property.
Criteria for Type II Stormwater Plans:
Lots that are required to submit a Type II Stormwater Plan have comparatively higher percentages
of impervious area and may require a more detailed design. These plans are also required to
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demonstrate that stormwater will be directed to appropriate locations without impacting
neighboring properties.
Due to the increased complexity of Type II Stormwater Plans and the requirement for volumetric
calculations for a design storm, this amendment requires that Type II Stormwater Plans shall be
designed by a professional engineer licensed in the state of Florida.
Type II Stormwater Plans are required to demonstrate:
Compliance with all Type I Stormwater Plan criteria. The Type I Stormwater Plan
criteria are designed to ensure stormwater runoff does not impact neighboring properties.
These criteria also apply to Type II Stormwater Plans.
An engineer’s analysis including:
o Water quantity calculations for a 5-year, 1-day storm event (the same design
storm event used in the current standards). Retention for the storm event is required
for the impervious area in excess of the thresholds for Type II Stormwater Plans
only. The DSAC-LDR Subcommittee determined that this storm event provides
adequate protection when applied to the area exceeding impervious area thresholds.
There is no requirement for water quality calculations included in this standard.
o A matrix of all required separation distances. This requirement will ensure that
the location of wells, drainfield systems, and stormwater retention or detention
areas are coordinated.
Certification of Compliance. The engineer is required to submit a certification of
compliance prior to inspections. Stormwater plans will be inspected during the 800 series
inspections for building permits. This is the same process used to inspect current
stormwater plans.
Application requirements
Application requirements for stormwater plans are established in the Administrative Code and are
designed to ensure that staff is provided with enough information to determine that appropriate
methods are used to direct discharge off site or to retain water on site.
Inspection and maintenance
The proposed amendment identifies an inspection schedule and maintenance requirements for
stormwater plans. Stormwater plans will be submitted with the building permit and will be
inspected by the County at the time of the building permit inspections and prior to the issuance of
a certificate of occupancy or certificate of completion, as applicable. Once approved, the property
owner is responsible for maintaining the site grading and drainage (such as the swales, French
drains, grates, etc.) in accordance with the approved stormwater plan. Since some types of site
work and impervious surfaces are not required to obtain a permit, this section also notifies property
owners that changes to the property, whether or not a permit is required, shall not modify the site
in a manner that will prevent the site from continuing to drain in accordance with the approved
stormwater plans.
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Violations
The amendment also proposes to establish stormwater plans as the tool for demonstrating
compliance with Collier County Code of Laws and Ordinances section 90-41 (f)(8) which states:
“…Subsequent to the construction of a single-family residence on the respective lot
(parcel of land), it shall be a violation of this article to cause ‘additional surface
water’ to run onto any real property owned by another landowner by filling, grading
or otherwise raising the elevation of the respective water source single family
residence lot…”
Staff is frequently called upon to investigate stormwater management issues on lots that were
developed prior to the establishment of the stormwater plan requirements. These types of
violations occur for a number of reasons including the addition of fill or slopes near the property
line. Therefore, this change will ensure that property owners and staff have a method to
demonstrate compliance with the Code of Laws.
DSAC-LDR SUBCOMMITTEE RECOMMENDATIONS: No changes, approved
unanimously on November 29, 2016.
DSAC RECOMMENDATIONS: No changes, approved unanimously on December 7, 2016.
PLANNING COMMISSION RECOMMENDATIONS: No changes, approved unanimously
on January 30, 2017.
FISCAL & OPERATIONAL IMPACTS: There are no anticipated fiscal or operational impacts
associated with this amendment.
RELATED CODES OR REGULATIONS:
Collier County Code of Laws and Ordinances section 90-41 (f)(8)
Florida Statutes Chapter 381.0065(4)(s)
GROWTH MANAGEMENT PLAN IMPACT: There are no anticipated Growth Management
Plan impacts associated with this amendment.
OTHER NOTES/VERSION DATE: Prepared by Jeremy Frantz, Senior Planner, 12/1/16.
Amend the LDC as follows:
6.05.01 Water Management Requirements 1
A complete stormwater management system shall be provided for all areas within the 2
subdivision or development, including lots, streets, and alleys. 3
A. The system design shall meet the applicable provisions of the current County codes and 4
ordinances, SFWMD rules and regulations pursuant to Florida Statutes, and the Florida 5
Administrative Code, and any other affected state and federal agencies' rules and 6
regulations in effect at the time of preliminary subdivision plat submission. Water 7
management areas will be required to be maintained in perpetuity according to the 8
9.B.a
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approved plans. Water management areas not maintained will be corrected according to 1
approved plans within 30 days. 2
B. Where stormwater runoff from outside the subdivision or development historically 3
passes on, over, or through areas of the subdivision or development, such runoff shall 4
be included in the stormwater system design. The system shall be designed for long life, 5
low cost maintenance by normal methods and provide for optimal on-site detention of 6
stormwater runoff and groundwater recharge in accordance with applicable County and 7
SFWMD regulations. 8
C. Any structure with an outside wall which is closer than 10 feet from a side property line 9
shall install properly sized (minimum twenty-four-square inch cross-section) gutters and 10
downspouts to direct stormwater away from neighboring properties and toward front 11
and/or rear swales or retention/detention areas. 12
D. In-ground percolation type retention systems such as rock trenches, exfiltration trenches 13
or beds, infiltrator type systems, gallery type systems, etc., shall not be used to achieve 14
water quality retention for residential subdivisions. Rear yard open retention systems 15
shall likewise not be designed to achieve water quality retention on projects submitted 16
after January 1, 2002. All retention systems for projects designed after January 1, 2002, 17
shall be on common property owned and maintained by a homeowners' association or 18
similar entity. 19
E. Any canal which forms a part of the public water management system shall be dedicated 20
for care and maintenance per the requirements of the governmental agency which has 21
jurisdiction. Canals located entirely within the subdivision and which do not form a part 22
of the public water management system shall be dedicated to the public, without the 23
responsibility for maintenance, as a drainage easement. A maintenance easement, of a 24
size acceptable to the County Manager or designee or other governmental agency with 25
maintenance responsibility, shall be provided adjacent to the established drainage 26
easement, or the drainage easement created must be of a size suitable for the 27
proposed canal and its maintenance. 28
F. Stormwater Retention/Detention Design for Single-Family Dwelling Units, Two-Family 29
Dwelling Units and Duplexes. 30
1. Applicability. Any application for a building permit to allow the development or 31
redevelopment of a single-family or two-family dwelling or duplex submitted 32
after July 1, 2008, except for the following conditions: 33
a. Any application within the boundaries of development projects that have: 34
(1) been permitted by the South Florida Water Management District for 35
Surface Water Management or Environmental Resource Protection and 36
(2) have a central surface water management collection, storage, 37
treatment and discharge system; 38
b. A one-time addition is allowed for certain sized homes, as set forth below; 39
or 40
c. An application accompanied by a stormwater management plan, signed 41
and sealed by a registered Florida Professional Engineer. 42
Table 6.05.01 F. 43
Lot Size Lot Coverage Impervious Area Coverage
Under 11,000 sq. ft. 25% 40%
11,000 sq. ft. to 52,999 sq. ft.
and 100 ft. or greater in width
2,750 sq. ft. +5% of area in
excess of 11,000 sq. ft.
4,400 sq. ft. +5% of area in
excess of 11,000 sq. ft.
11,000 sq. ft. to 52,999 sq. ft.
and less than 100 ft. in width
2,750 sq. ft. +2% of area in
excess of 11,000 sq. ft.
4,400 sq. ft. +2% of area in
excess of 11,000 sq. ft.
9.B.a
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53,000 sq. ft. and over 4,850 sq. ft. +3% of area in
excess of 53,000 sq. ft.
6,500 sq. ft. +2% of area in
excess of 53,000 sq. ft.
1
2. The maximum allowable ratio of lot coverage and impervious area coverage to 2
the total lot area shall be as provided for in Table 6.05.01 F. unless accompanied 3
by an engineer's analysis as specified below. 4
a. The site drainage analysis shall include water quality calculations to 5
SFWMD standards and water quantity calculations done to accommodate 6
the runoff, from area in excess of the above ratio, from a 5-year 1-day 7
storm and shall include a percolation test done by a qualified engineer or 8
technician. If the site will use a drainfield/septic tank for sewage 9
treatment/disposal, the wet season water table calculations for drainage 10
must match that used for the drainfield design. 11
b. The application site plan shall list all required separation distances 12
between wells, drainfield systems, and stormwater retention/detention 13
areas. The calculations may be done on the site plan or may be in a 14
separate Engineer's report, but must be signed and sealed by the 15
Engineer. 16
c. The water surface area of swimming pools and ponds is not considered 17
as impervious area for the purposes of the calculations in Table 6.05.01 18
F. 19
3. A one-time addition to an existing residence will be allowed after July 1, 2008. 20
The addition will be limited to 3 percent of the lot area up to a maximum of 1,000 21
square feet as long as that one-time addition does not exceed the area in Table 22
6.05.01 F. by more than 3 percent of the lot area or more than 1,000 square feet. 23
GF. The design of the stormwater management system shall fully incorporate the 24
requirements of the Interim Watershed Management regulations of LDC section 3.07.00. 25
HG. Street grades. Street grades must be determined in relation to the drainage facilities 26
for the subdivision and must not exceed four percent nor be less than 0.3 percent, 27
unless otherwise approved by the County Manager or designee pursuant to section 28
10.02.04 of the LDC. Street grades must be shown on the development plans by 29
direction and percent of fall on the road profiles. 30
IH. Rainfall and runoff criteria. The system must be designed for "design floods" resulting 31
from rain storms and antecedent conditions for all system components in accordance 32
with current Collier County and South Florida Water Management District criteria. 33
1. Runoff coefficients. Existing land usage will be considered for the selection of 34
proper runoff coefficients within the drainage basins involved, whether within the 35
subdivision or development or not. 36
2. Lakes. Artificial lakes and retention basins proposed as part of a stormwater 37
retention system for on-site water management must be designed and shall be 38
consistent with other ordinances or regulations of Collier County, the state or the 39
region. All lakes will be set back from abutting roadways or intersections 40
pursuant to the design standards established in sections 22-106 through 22-119 41
of the Code of Laws and Ordinances. 42
JI. Stormwater outfalls. Stormwater runoff must be conducted to positive outfalls that can be 43
permanently maintained, practicably and legally. Outfalls to existing waterways, canals, 44
preserve or conservation areas, lakes or storm sewers will be acceptable provided it can 45
be demonstrated through a professional engineering study to the County Manager or 46
designee that such receiving systems have adequate capacity to receive the proposed 47
quantity and quality of the additional flow. 48
9.B.a
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1. Side ditches or swales along public or private roads shall not be accepted as 1
suitable positive outfalls except as may be specifically accepted under the 2
provisions of the LDC by the County Manager or designee and by the Florida 3
Department of Transportation, if applicable. The storage of stormwater runoff in 4
other existing or proposed ditches or swales within a public or private right-of-5
way will be permitted for volume storage when approved under South Florida 6
Water Management District design criteria, but will not be utilized to satisfy the 7
stormwater storage (quality) requirements of a development's master water 8
management system. 9
KJ. Major waterway. Improvement or establishment of major waterways and canals will be 10
developed in full accord with applicable stormwater management criteria. Engineering 11
data, criteria, and suitable calculations shall be submitted to the County Manager or 12
designee prior to approval of construction plans. 13
1. Roadways over major waterways will be structures approved by the County 14
Manager or designee, sized to maintain flow capacity, designed to assure long 15
life and minimal maintenance. Construction must meet all current Florida 16
Department of Transportation Standard Specifications for Road and Bridge 17
Construction, as amended, unless otherwise approved by the County Manager or 18
designee pursuant to section 10.02.04 of the LDC. 19
LK. Outfall ditches and open channels. Unless otherwise approved by the County Manager 20
or designee pursuant to section 10.02.04 of the LDC, side slopes no steeper than four to 21
one will be allowed. Protection against scour and erosion will be provided as required by 22
the County Manager or designee. 23
ML. Roadside swales. 24
1. Design. In the interest of preserving the existing natural groundwater levels, 25
roadways will not be designed so as to cause the significant lowering of the water 26
levels existing in the area prior to development. Roadside swales and ditches 27
may be permitted within street rights-of-way where the use of roadside swales 28
can be justified to the County Manager or designee through a written report 29
prepared by the applicant's professional engineer. Swales, where permissible, 30
will have side slopes no steeper than four to one and they will not be utilized to 31
satisfy the stormwater quality (volume) requirements of a project's master water 32
management system. Where flow velocities in excess of four feet per second are 33
anticipated, urban right-of-way sections will be required. 34
2. Erosion protection. All unpaved areas within the permanent right-of-way must 35
be provided with permanent erosion protection, such as native vegetation or 36
turf. Swale ditches shall be sodded a lateral distance extending from the road 37
pavement to the top of the swale ditch backslope. Where valley guttered sections 38
are used for drainageways, turf protection must be placed from the edge of the 39
gutter to the outer limits of the right-of-way. If seeding is utilized, then mulching 40
in accordance with the Florida Department of Transportation standards will be 41
required. Additionally, if seeding and mulching are utilized, then a strip of sod one 42
foot wide will be placed along the face of the pavement or curb section and over 43
the invert of any approved swale section within the runoff flowway. All swales 44
subject to erosion velocities will have adequate erosion protection in the form of 45
riprap or other applicable like methods. 46
3. Driveways across swale ditches. Driveways across permitted swale ditches 47
must have placed beneath them drainage pipes of adequate size and type 48
approved by the County Manager or designee, based on the capacity 49
requirements calculated by the applicant's professional engineer for the 50
development's master water management system. 51
9.B.a
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NM. Street drainage. Street drainage within the road right-of-way through grassed swales 1
will be permitted for rural cross sections only except where velocities in excess of four 2
feet per second are anticipated. The flow from these swales or other types of drainage 3
facilities will be diverted to natural percolation areas, artificial seepage basins or 4
artificial lakes of at least sufficient capacity to comply with the criteria of Collier County 5
and the South Florida Water Management District. Other equally effective methods of 6
returning cleansed waters to the aquifer will be acceptable upon prior review and 7
approval by the County Manager or designee. 8
1. Existing natural lakes may be used as detention areas provided that they have 9
adequate storage capacity and that pretreatment measures approved by the 10
County Manager or designee are taken to prevent pollutant matter from entering 11
the lake. Positive outfall drainage facilities will be provided away from all 12
percolation areas, seepage basins, detention areas and artificial lakes to handle 13
the runoff from storms which exceed the required design storm event in duration 14
and/or severity. 15
ON. Percolation areas. The actual area required will depend on the percolation rate for the 16
soils at the specific site and the manner in which the site is developed in accordance 17
with Collier County and South Florida Water Management District criteria. 18
1. Underground drainage. Where drainage plans provide for, or it is so directed by 19
the County Manager or designee, the collection of stormwater in underground 20
pipes, inlets and other appurtenances for conveyance to an intermediate or 21
ultimate outfall, the following minimum design criteria will be observed: 22
a. The minimum pipe used within a publicly maintained stormwater 23
collection system will be 15 inches in diameter. 24
b. Inlets will be spaced at such intervals and in such a manner to allow for 25
the acceptance of 100 percent of the ten-year, one-hour storm runoff. 26
c. The distance between terminating and intermediate structures must not 27
exceed those required by the Florida Department of Transportation, 28
pursuant to Florida Department of Transportation Drainage Manual, 29
Volumes 1—4 (1987 edition or latest revision). 30
d. The stormwater, underground collection system, must be so designed 31
that the elevation of the hydraulic gradient during a ten-year, one-hour 32
storm event is never higher than the crown elevation of any publicly 33
maintained roadway in the system. 34
e. The pipes must be designed to minimize sediment deposits. 35
f. The pipe materials must meet the requirements set forth in sections 36
943—948 inclusive of the current edition of the Florida Department of 37
Transportation Standard Specifications for Road and Bridge Construction. 38
Only concrete pipe or other pipe materials approved by the County 39
Manager or designee may be used in tidal or salt waters. 40
g. All drainage pipes must be fitted with headwalls, endwalls, inlets and 41
other appropriate terminating and intermediate structures. 42
PO. Stormwater disposal. The method of ultimate disposal of stormwaters will be dependent 43
upon the soil characteristic underlying the development or subdivision. All stormwaters 44
will be subjected to treatment for the removal of petroleum residues, oils, suspended 45
solids and other pollutants found in stormwater runoff. The method of treatment will be 46
determined by the applicant's professional engineer responsible for the preparation of 47
the stormwater management plans and specifications, and will be subject to the approval 48
of the County Manager or designee and the concerned state agencies. 49
# # # # # # # # # # # # # 50
51
9.B.a
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6.05.03 Stormwater Plans for Single-Family Dwelling Units, Two-Family Dwelling Units, 1
and Duplexes 2
A. Purpose. The purpose of this section is to manage stormwater runoff on lots with 3
single-family dwelling units, two-family dwelling units, or duplexes in order to 4
prevent detrimental impacts on site or to adjacent properties. This section is also 5
designed to provide criteria for demonstrating compliance with Collier County Code of 6
Laws and Ordinances section 90-41(f)(8). For the purposes of this section, the term 7
impervious area shall include roofed buildings, concrete and asphalt pads, cool deck 8
(e.g. spraycrete), pavers with limerock base, swimming pools, and lined pond area. 9
Additionally, the term pervious area shall include grass, crushed stone (e.g. #57), 10
mulch, pavers without limerock base, and unlined pond area. 11
B. Applicability. A Type I or Type II Stormwater Plan shall be required for lots with single-12
family dwellings, two-family dwellings, or duplexes with the following exceptions: 13
1. Lots located in the Rural Agricultural (A) zoning district outside the Immokalee 14
Urban Area Overlay district and outside the coastal urban designated area as 15
established in the Future Land Use Map. 16
2. Lots that have received a Surface Water Management or Environmental 17
Resource Protection permit from the South Florida Water Management District. 18
C. Stormwater plan submittal. A stormwater plan shall be submitted as part of an 19
application for a building permit for any of the following: 20
1. Type I Stormwater Plans. 21
a. New structures, additions, pools, or decks on lots with 40 percent or 22
less impervious area, or as described in the following zoning districts: 23
i. RSF-1 zoned lots with 30 percent or less impervious area. 24
ii. Rural Agricultural (A) zoned lots within the Immokalee Urban Area 25
Overlay district or within the coastal urban designated area as 26
established in the Future Land Use Map with 30 percent or less 27
impervious area. 28
iii. Estates zoned lots with 25 percent or less impervious area. 29
b. New structures, additions, pools, or decks on lots that discharge directly 30
to a waterbody downstream of the last control structure, whether or not 31
the lot exceeds the impervious area thresholds in LDC section 6.05.03 32
C.1.a above. 33
2. Type II Stormwater Plans. 34
a. New structures, additions, pools, or decks on lots with more than 40 35
percent impervious area, or as described in the following zoning 36
districts: 37
i. RSF-1 zoned lots with more than 30 percent impervious area. 38
ii. Rural Agricultural (A) zoned lots within the Immokalee Urban Area 39
Overlay district or within the coastal urban designated area as 40
established in the Future Land Use Map with more than 30 41
percent impervious area. 42
iii. Estates zoned lots with more than 25 percent impervious area. 43
b. New structures, additions, pools, or decks on lots that discharge directly 44
to a waterbody upstream of the last control structure, whether or not the 45
lot exceeds the impervious area thresholds in LDC section 6.05.03 46
C.2.a above. 47
D. Stormwater plan criteria. 48
1. Type I Stormwater Plan. Type I Stormwater Plans shall be prepared by a Florida 49
registered design professional, licensed contractor or owner builder. The Type I 50
Stormwater Plan shall demonstrate the following: 51
9.B.a
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a. Stormwater runoff. Discharges from the impacted area shall be directed 1
into one or more of the following: 2
i. An existing surface water management system. 3
ii. A drainage conveyance system, such as swales or underground 4
storm sewer systems. 5
iii. On-site retention or detention areas. The bottom of retention or 6
detention areas shall be above the wet season water table. 7
iv. A waterbody downstream of the last control structure. Stormwater 8
discharges to a waterbody shall not result in erosion of soil. 9
Discharges may be allowed through an orifice with a minimum 10
size of 3 inches and the soil adjacent to the discharge area shall 11
be stabilized. For lots discharging directly to waterbodies 12
upstream of the last control structure, see LDC section 6.05.03 13
D.2. 14
b. Design standards. 15
i. Retaining walls shall be set back six inches from the property line, 16
if applicable. 17
ii. Stone in French drains shall be calculated with a 40 percent void 18
ratio, if applicable. 19
iii. Stormwater pipes, if used, shall not be metal. 20
iv. Gutters and downspouts shall comply with LDC section 6.05.01 C, 21
if applicable. 22
c. The location, dimension, and setbacks of septic systems, if applicable. 23
2. Type II Stormwater Plan. Type II Stormwater Plans shall be prepared by a 24
professional engineer licensed in the state of Florida. The Type II Stormwater 25
Plan shall demonstrate the following: 26
a. Stormwater runoff. Discharges from the impacted area shall be directed 27
into one or more of the following: 28
i. An existing surface water management system. 29
ii. A drainage conveyance system, such as swales or underground 30
storm sewer systems. 31
iii. On-site retention or detention areas. The bottom of retention or 32
detention areas shall be above the wet season water table. 33
iv. A waterbody. Stormwater discharges directly to a waterbody shall 34
not result in erosion of soil. Discharges may be allowed through 35
an orifice with a minimum size of 3 inches and the soil adjacent to 36
the discharge area shall be stabilized. 37
b. Design standards. 38
i. Retaining walls shall be set back six inches from the property line, 39
if applicable. 40
ii. Stone in French drains shall be calculated with a 40 percent void 41
ratio, if applicable. 42
iii. Stormwater pipes, if used, shall not be metal. 43
iv. Gutters and downspouts shall comply with LDC section 6.05.01 C, 44
if applicable. 45
c. The location, dimension, and setbacks of septic systems, if applicable. 46
d. An engineer’s analysis that demonstrates the following: 47
i. Water quantity calculations by a qualified engineer or technician 48
that demonstrate the ability to accommodate the runoff from the 49
area exceeding the applicable threshold in LDC section 6.05.03 C 50
from a 5-year 1-day storm. 51
9.B.a
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ii. A matrix of all required separation distances between wells, 1
drainfield systems, and stormwater retention/detention areas. The 2
calculations may be done on the site plan or may be in a separate 3
engineer's report, but the site plan must be signed and sealed by 4
a professional engineer licensed in the state of Florida. 5
e. A certification of compliance shall be submitted to the County by the 6
engineer prior to an inspection. 7
E. Application submittal requirements. The Administrative Code shall establish the 8
submittal requirements for stormwater plans. 9
F. Inspection and maintenance. 10
1. Inspection. The subject property shall be inspected by the County prior to 11
issuance of a certificate of occupancy or certificate of completion, as applicable, 12
for consistency with the approved stormwater plan. 13
2. Maintenance. The property owner shall maintain site grading and drainage (e.g. 14
swales, French drains, grates, etc.) in accordance with the approved stormwater 15
plan. Future changes to impervious area or site grading shall not modify the site 16
in a manner that will prevent continued drainage of the site as shown on the 17
approved stormwater plan, whether or not a permit is required for an 18
improvement. 19
G. Violations. Where a violation of Collier County Code of Laws and Ordinances section 90-20
41(f)(8) has been found by the Code Enforcement Board or Special Magistrate, a 21
stormwater plan shall be submitted that demonstrates the additional flow of surface 22
water has been eliminated. The subject property shall be inspected by the County to 23
determine if the violation has been resolved. 24
# # # # # # # # # # # # # 25
9.B.a
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Collier County Land Development Code | Administrative Procedures Manual
Chapter 4 | Administrative Procedures
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M. Stormwater Plan
Reference LDC subsection 6.05.03.
Applicability This process applies to single-family dwellings, two-family dwellings, and duplexes that
meet the applicability criteria established in LDC section 6.05.03.
This process may also be used to demonstrate compliance with Collier County Code of
Laws and Ordinances section 90-41(f)(8) as described in LDC section 6.05.03 G.
Pre-application A pre-application meeting is not required.
Initiation The applicant submits a Type I or Type II Stormwater Plan as part of the Building Permit
application or when required by the Code Enforcement Board or Special Magistrate to
demonstrate compliance with Collier County Code of Laws and Ordinances section 90-
41(f)(8).
Application
Contents
Submittal Credentials: A Type I Stormwater Plan, as described below, shall be prepared
by a Florida registered design professional, licensed contractor, or owner
builder. A Type II Stormwater Plan, as described below, shall be prepared by a
professional engineer licensed in the state of Florida. The name and contact
information of the person who prepared the drainage plan shall be included on
the document.
Type I and Type II Stormwater Plan applications must include the following:
1. Applicant contact information.
2. Property information, including:
Address of the subject property;
Zoning of the subject property; and
Description of the proposed activity.
3. The Stormwater Plan shall demonstrate the following:
Property boundaries;
Lot area;
Finished floor elevation of the subject property, as needed;
Elevation of adjacent properties at the property line and representative
elevations of the subject site throughout the impacted area, as needed;
Location and area of all surfaces that prevent the percolation or absorption
of water into the ground on the site;
Septic system location and dimensions, if applicable;
Location of existing topographical features, such as, watercourses, drainage
ditches, lakes, marshes, if applicable;
Proposed drainage directional arrows;
Location and type of all drainage infrastructure, if applicable;
9.B.b
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Chapter 4 | Administrative Procedures
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Square feet of retention or detention areas, if applicable;
Depth of retention or detention areas in inches, if applicable;
Cross-sections illustrating proposed grading and drainage infrastructure,
including but not limited to: berms, walls, swales, pipes, gutters and
downspouts, or other drainage facilities as needed to demonstrate
compliance with LDC section 6.05.03; and
Elevation of the wet season water table in the impacted area if detention or
retention is proposed;
In addition to the application contents above, Type II Stormwater Plans must
include an engineer’s analysis that demonstrates the following:
Water quantity calculations required in LDC section 6.05.03 D.2;
A matrix of all required separation distances between wells, drainfield
systems, and stormwater retention/detention areas. The matrix may be
included as a part of the site plan or on a separate engineer’s report; and
The wet season water table elevation.
4. Any additional information related to the subject site, impervious areas, or drainage
requested by the County Manager or designee.
Completeness and
Processing
The Planning & Zoning Division will review the application for completeness. After
submission of the completed application packet accompanied with the required fee, the
applicant will receive a mailed or electronic response notifying the applicant that the
petition is being processed. Accompanying that response will be a receipt for the
payment and the tracking number (i.e., XX201200000) assigned to the petition. This
petition tracking number should be noted on all future correspondence regarding the
petition.
Notice No notice is required.
Public Hearing No public hearing required.
Decision maker The County Manager or designee.
Review Process The Stormwater Plan will be reviewed by the Planning & Zoning Division as a part of the
Building Permit application or a code enforcement case.
Updated
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ORDINANCE NO. 17 - ____
AN ORDINANCE OF THE BOARD OF COUNTY COMMISSIONERS OF
COLLIER COUNTY, FLORIDA, AMENDING ORDINANCE NUMBER 04 -
41, AS AMENDED, THE COLLIER COUNTY LAND DEVELOPMENT
CODE, WHICH INCLUDES THE COMPREHENSIVE LAND
REGULATIONS FOR THE UNINCORPORATED AREA OF COLLIER
COUNTY, FLORIDA, BY PROVIDING FOR: SECTION ONE, RECITALS;
SECTION TWO, FINDINGS OF FACT; SECTION THREE, ADOPTION
OF AMENDMENTS TO THE LAND DEVELOPMENT CODE, MORE
SPECIFICALLY AMENDING THE FOLLOWING: CHAPTER SIX –
INFRASTRUCTURE IMPROVEMENTS AND ADEQUATE PUBLIC
FACILITIES REQUIREMENTS, INCLUDING SECTION 6.05.01 WATER
MANAGEMENT REQUIREMENTS, ADDING SECTION 6.05.03
STORMWATER PLANS FOR SINGLE-FAMILY DWELLING UNITS,
TWO-FAMILY DWELLING UNITS, AND DUPLEXES; SECTION FOUR,
CONFLICT AND SEVERABILITY; SECTION FIVE, INCLUSION IN THE
COLLIER COUNTY LAND DEVELOPMENT CODE; AND SECTION SIX,
EFFECTIVE DATE.
Recitals
WHEREAS, on October 30, 1991, the Collier County Board of County Commissioners
adopted Ordinance No. 91-102, the Collier County Land Development Code (hereinafter LDC),
which was subsequently amended; and
WHEREAS, the Collier County Board of County Commissioners (Board) on June 22,
2004, adopted Ordinance No. 04-41, which repealed and superseded Ordinance No. 91-102, as
amended, the Collier County Land Development Code, which had an effective date of October
18, 2004; and
WHEREAS, the LDC may not be amended more than two times in each calendar year
unless additional amendment cycles are approved by the Collier County Board of
Commissioners pursuant to Section 10.02.09 A. of the LDC; and
WHEREAS, this amendment to the LDC is part of the first amendment cycle for the
calendar year 2016; and
WHEREAS, on March 18, 1997, the Board adopted Resolution 97-177 establishing local
requirements and procedures for amending the LDC; and
WHEREAS, all requirements of Resolution 97-177 have been met; and
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WHEREAS, the Board of County Commissioners, in a manner prescribed by law, did
hold advertised public hearings on March 14, 2017 and April 11, 2017, and did take action
concerning these amendments to the LDC; and
WHEREAS, the subject amendments to the LDC are hereby determined by this Board to
be consistent with and to implement the Collier County Growth Management Plan as required
by Subsections 163.3194 (1) and 163.3202 (1), Florida Statutes; and
WHEREAS, this ordinance is adopted in compliance with and pursuant to the
Community Planning Act (F.S. § 163.3161 et seq.), and F.S. § 125.01(1)(t) and (1)(w); and
WHEREAS, this ordinance is adopted pursuant to the constitutional and home rule
powers of Fla. Const. Art. VIII, § 1(g); and
WHEREAS, all applicable substantive and procedural requirements of the law have
otherwise been met.
NOW, THEREFORE BE IT ORDAINED by the Board of County Commissioners of
Collier County, Florida, that:
SECTION ONE: RECITALS
The foregoing Recitals are true and correct and incorporated by reference herein as if
fully set forth.
SECTION TWO: FINDINGS OF FACT
The Board of Commissioners of Collier County, Florida, hereby makes the following
findings of fact:
1. Collier County, pursuant to § 163.3161, et seq., F.S., the Florida Community
Planning Act (herein after the “Act”), is required to prepare and adopt a comprehensive plan.
2. After adoption of the Comprehensive Plan, the Act and in particular §
163.3202(1). F.S., mandates that Collier County adopt land development regulations that are
consistent with and implement the adopted comprehensive plan.
3. Section 163.3201, F.S., provides that it is the intent of the Act that the adoption
and enforcement by Collier County of land development regulations for the total unincorporated
area shall be based on, be related to, and be a means of implementation for, the adopted
comprehensive plan.
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4. Section 163.3194(1)(b), F.S., requires that all land development regulations
enacted or amended by Collier County be consistent with the adopted comprehensive plan, or
element or portion thereof, and any land regulations existing at the time of adoption which are
not consistent with the adopted comprehensive plan, or element or portion thereof, shall be
amended so as to be consistent.
5. Section 163.3202(3), F.S., states that the Act shall be construed to encourage
the use of innovative land development regulations.
6. On January 10, 1989, Collier County adopted the Collier County Growth
Management Plan (hereinafter the “Growth Management Plan” or “GMP”) as its comprehensive
plan pursuant to the requirements of § 163.3161 et seq., F.S.
7. Section 163.3194(1)(a), F.S., mandates that after a comprehensive plan, or
element or portion thereof, has been adopted in conformity with the Act, all development
undertaken by, and all actions taken in regard to development orders by, governmental
agencies in regard to land covered by such comprehensive plan, or element or portion thereof
shall be consistent with such comprehensive plan or element or portion thereof.
8. Pursuant to § 163.3194(3)(a), F.S., a development order or land development
regulation shall be consistent with the comprehensive plan if the land uses, densities or
intensities , capacity or size, timing, and other aspects of development are compatible with, and
further the objectives, policies, land uses, densities, or intensities in the comprehensive plan
and if it meets all other criteria enumerated by the local government.
9. Section 163.3194(3)(b), F.S., states that a development approved or undertaken
by a local government shall be consistent with the comprehensive plan if the land uses,
densities or intensities, capacity or size, timing, and other aspects of development are
compatible with, and further the objectives, policies, land uses, densities, or intensities in the
comprehensive plan and if it meets all other criteria enumerated by the local government.
10. On October 30, 1991, Collier County adopted the Collier County Land
Development Code, which became effective on November 13, 1991. The Land Development
Code adopted in Ordinance 91-102 was recodified and superseded by Ordinance 04-41.
11. Collier County finds that the Land Development Code is intended and necessary
to preserve and enhance the present advantages that exist in Collier County; to encourage the
most appropriate use of land, water and resources consistent with the public interest; to
overcome present handicaps; and to deal effectively with future problems that may result from
the use and development of land within the total unincorporated area of Collier County and it is
intended that this Land Development Code preserve, promote, protect and improve the public
health, safety, comfort, good order, appearance, convenience and general welfare of Collier
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County; to prevent the overcrowding of land and avoid the undue concentration of population; to
facilitate the adequate and efficient provision of transportation, water, sewerage, schools,
parks, recreational facilities, housing and other requirements and services; to conserve,
develop, utilize and protect natural resources within the jurisdiction of Collier County; to protect
human, environmental, social and economic resources; and to maintain through orderly growth
and development, the character and stability of present and future land uses and development
in Collier County.
12. It is the intent of the Board of County Commissioners of Collier County to
implement the Land Development Code in accordance with the provisions of the Collier County
Comprehensive Plan, Chapter 125, Fla. Stat., and Chapter 163, Fla. Stat., and through these
amendments to the Code.
SECTION THREE: ADOPTION OF AMENDMENTS TO THE LAND DEVELOPMENT
CODE
* * * * * * * * * * * * *
SUBSECTION 3.A. AMENDMENTS TO SECTION 6.05.01 WATER MANAGEMENT
REQUIREMENTS
Section 6.05.01 Water Management Requirements, of Ordinance 04-41, as amended, the
Collier County Land Development Code, is hereby amended to read as follows:
Section 6.05.01 Water Management Requirements
* * * * * * * * * * * *
E. Any canal which forms a part of the public water management system shall be dedicated
for care and maintenance per the requirements of the governmental agency which has
jurisdiction. Canals located entirely within the subdivision and which do not form a part
of the public water management system shall be dedicated to the public, without the
responsibility for maintenance, as a drainage easement. A maintenance easement, of a
size acceptable to the County Manager or designee or other governmental agency with
maintenance responsibility, shall be provided adjacent to the established drainage
easement, or the drainage easement created must be of a size suitable for the
proposed canal and its maintenance.
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F. Stormwater Retention/Detention Design for Single-Family Dwelling Units, Two-Family
Dwelling Units and Duplexes.
1. Applicability. Any application for a building permit to allow the development or
redevelopment of a single-family or two-family dwelling or duplex submitted
after July 1, 2008, except for the following conditions:
a. Any application within the boundaries of development projects that have:
(1) been permitted by the South Florida Water Management District for
Surface Water Management or Environmental Resource Protection and
(2) have a central surface water management collection, storage,
treatment and discharge system;
b. A one-time addition is allowed for certain sized homes, as set forth below;
or
c. An application accompanied by a stormwater management plan, signed
and sealed by a registered Florida Professional Engineer.
Table 6.05.01 F.
Lot Size Lot Coverage Impervious Area Coverage
Under 11,000 sq. ft. 25% 40%
11,000 sq. ft. to 52,999 sq. ft.
and 100 ft. or greater in width
2,750 sq. ft. +5% of area in
excess of 11,000 sq. ft.
4,400 sq. ft. +5% of area in
excess of 11,000 sq. ft.
11,000 sq. ft. to 52,999 sq. ft.
and less than 100 ft. in width
2,750 sq. ft. +2% of area in
excess of 11,000 sq. ft.
4,400 sq. ft. +2% of area in
excess of 11,000 sq. ft.
53,000 sq. ft. and over 4,850 sq. ft. +3% of area in
excess of 53,000 sq. ft.
6,500 sq. ft. +2% of area in
excess of 53,000 sq. ft.
2. The maximum allowable ratio of lot coverage and impervious area coverage to
the total lot area shall be as provided for in Table 6.05.01 F. unless accompanied
by an engineer's analysis as specified below.
a. The site drainage analysis shall include water quality calculations to
SFWMD standards and water quantity calculations done to accommodate
the runoff, from area in excess of the above ratio, from a 5 -year 1-day
storm and shall include a percolation test done by a qualified engineer or
technician. If the site will use a drainfield/septic tank for sewage
treatment/disposal, the wet season water table calculations for drainage
must match that used for the drainfield design.
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b. The application site plan shall list all required separation distances
between wells, drainfield systems, and stormwater retention/detention
areas. The calculations may be done on the site plan or may be in a
separate Engineer's report, but must be signed and sealed by the
Engineer.
c. The water surface area of swimming pools and ponds is not considered
as impervious area for the purposes of the calculations in Table 6.05.01
F.
3. A one-time addition to an existing residence will be allowed after July 1, 2008.
The addition will be limited to 3 percent of the lot area up to a maximum of 1,000
square feet as long as that one-time addition does not exceed the area in Table
6.05.01 F. by more than 3 percent of the lot area or more than 1,000 square feet.
G F. The design of the stormwater management system shall fully incorporate the
requirements of the Interim Watershed Management regulations of LDC section 3.07.00.
(**ALL REMAINING SUBSECTIONS TO BE RE-LETTERED ACCORDINGLY**)
* * * * * * * * * * * * *
SUBSECTION 3.B. ADDING SECTION 6.05.03 STORMWATER PLANS FOR
SINGLE-FAMILY DWELLING UNITS, TWO-FAMILY DWELLING
UNITS, AND DUPLEXES
Section 6.05.03 Stormwater Plans for Single-Family Dwelling Units, Two-Family Dwelling Units,
and Duplexes, of Ordinance 04-41, as amended, the Collier County Land Development Code, is
hereby added as follows:
Section 6.05.03 Stormwater Plans for Single-Family Dwelling Units, Two-Family Dwelling Units,
and Duplexes
A. Purpose. The purpose of this section is to manage stormwater runoff on lots with
single-family dwelling units, two-family dwelling units, or duplexes in order to
prevent detrimental impacts on site or to adjacent properties. This section is also
designed to provide criteria for demonstrating compliance with Collier County Code of
Laws and Ordinances section 90-41(f)(8). For the purposes of this section, the term
impervious area shall include roofed buildings, concrete and asphalt pads, cool deck
(e.g. spraycrete), pavers with limerock base, swimming pools, and lined pond area.
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Additionally, the term pervious area shall include grass, crushed stone (e.g. #57),
mulch, pavers without limerock base, and unlined pond area.
B. Applicability. A Type I or Type II Stormwater Plan shall be required for lots with single-
family dwellings, two-family dwellings, or duplexes with the following exceptions:
1. Lots located in the Rural Agricultural (A) zoning district outside the Immokalee
Urban Area Overlay district and outside the coastal urban designated area as
established in the Future Land Use Map.
2. Lots that have received a Surface Water Management or Environmental
Resource Protection permit from the South Florida Water Management District.
C. Stormwater plan submittal. A stormwater plan shall be submitted as part of an
application for a building permit for any of the following:
1. Type I Stormwater Plans.
a. New structures, additions, pools, or decks on lots with 40 percent or
less impervious area, or as described in the following zoning districts:
i. RSF-1 zoned lots with 30 percent or less impervious area.
ii. Rural Agricultural (A) zoned lots within the Immokalee Urban Area
Overlay district or within the coastal urban designated area as
established in the Future Land Use Map with 30 percent or less
impervious area.
iii. Estates zoned lots with 25 percent or less impervious area.
b. New structures, additions, pools, or decks on lots that discharge directly
to a waterbody downstream of the last control structure, whether or not
the lot exceeds the impervious area thresholds in LDC section 6.05.03
C.1.a above.
2. Type II Stormwater Plans.
a. New structures, additions, pools, or decks on lots with more than 40
percent impervious area, or as described in the following zoning
districts:
i. RSF-1 zoned lots with more than 30 percent impervious area.
ii. Rural Agricultural (A) zoned lots within the Immokalee Urban Area
Overlay district or within the coastal urban designated area as
established in the Future Land Use Map with more than 30
percent impervious area.
iii. Estates zoned lots with more than 25 percent impervious area.
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b. New structures, additions, pools, or decks on lots that discharge directly
to a waterbody upstream of the last control structure, whether or not the
lot exceeds the impervious area thresholds in LDC section 6.05.03
C.2.a above.
D. Stormwater plan criteria.
1. Type I Stormwater Plan. Type I Stormwater Plans shall be prepared by a Florida
registered design professional, licensed contractor or owner builder. The Type I
Stormwater Plan shall demonstrate the following:
a. Stormwater runoff. Discharges from the impacted area shall be directed
into one or more of the following:
i. An existing surface water management system.
ii. A drainage conveyance system, such as swales or underground
storm sewer systems.
iii. On-site retention or detention areas. The bottom of retention or
detention areas shall be above the wet season water table.
iv. A waterbody downstream of the last control structure. Stormwater
discharges to a waterbody shall not result in erosion of soil.
Discharges may be allowed through an orifice with a minimum
size of 3 inches and the soil adjacent to the discharge area shall
be stabilized. For lots discharging directly to waterbodies
upstream of the last control structure, see LDC section 6.05.03
D.2.
b. Design standards.
i. Retaining walls shall be set back six inches from the property line,
if applicable.
ii. Stone in French drains shall be calculated with a 40 percent void
ratio, if applicable.
iii. Stormwater pipes, if used, shall not be metal.
iv. Gutters and downspouts shall comply with LDC section 6.05.01 C,
if applicable.
c. The location, dimension, and setbacks of septic systems, if applicable.
2. Type II Stormwater Plan. Type II Stormwater Plans shall be prepared by a
professional engineer licensed in the state of Florida. The Type II Stormwater
Plan shall demonstrate the following:
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a. Stormwater runoff. Discharges from the impacted area shall be directed
into one or more of the following:
i. An existing surface water management system.
ii. A drainage conveyance system, such as swales or underground
storm sewer systems.
iii. On-site retention or detention areas. The bottom of retention or
detention areas shall be above the wet season water table.
iv. A waterbody. Stormwater discharges directly to a waterbody shall
not result in erosion of soil. Discharges may be allowed through
an orifice with a minimum size of 3 inches and the soil adjacent to
the discharge area shall be stabilized.
b. Design standards.
i. Retaining walls shall be set back six inches from the property line,
if applicable.
ii. Stone in French drains shall be calculated with a 40 percent void
ratio, if applicable.
iii. Stormwater pipes, if used, shall not be metal.
iv. Gutters and downspouts shall comply with LDC section 6.05.01 C,
if applicable.
c. The location, dimension, and setbacks of septic systems, if applicable.
d. An engineer’s analysis that demonstrates the following:
i. Water quantity calculations by a qualified engineer or technician
that demonstrate the ability to accommodate the runoff from the
area exceeding the applicable threshold in LDC section 6.05.03 C
from a 5-year 1-day storm.
ii. A matrix of all required separation distances between wells,
drainfield systems, and stormwater retention/detention areas. The
calculations may be done on the site plan or may be in a separate
engineer's report, but the site plan must be signed and sealed by
a professional engineer licensed in the state of Florida.
e. A certification of compliance shall be submitted to the County by the
engineer prior to an inspection.
E. Application submittal requirements. The Administrative Code shall establish the
submittal requirements for stormwater plans.
F. Inspection and maintenance.
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1. Inspection. The subject property shall be inspected by the County prior to
issuance of a certificate of occupancy or certificate of completion, as applicable,
for consistency with the approved stormwater plan.
2. Maintenance. The property owner shall maintain site grading and drainage (e.g.
swales, French drains, grates, etc.) in accordance with the approved stormwater
plan. Future changes to impervious area or site grading shall not modify the site
in a manner that will prevent continued drainage of the site as shown on the
approved stormwater plan, whether or not a permit is required for an
improvement.
G. Violations. Where a violation of Collier County Code of Laws and Ordinances section 90-
41(f)(8) has been found by the Code Enforcement Board or Special Magistrate, a
stormwater plan shall be submitted that demonstrates the additional flow of surface
water has been eliminated. The subject property shall be inspected by the County to
determine if the violation has been resolved.
* * * * * * * * * * * * *
SECTION FOUR: CONFLICT AND SEVERABILITY
In the event that any provisions of this ordinance should result in an unresolved conflict
with the provisions of the Land Development Code (LDC) or Growth Management Plan (GMP),
the applicable provisions of the LDC or GMP shall prevail. In the event this Ordinance conflicts
with any other Ordinance of Collier County or other applicable law, the more restrictive shall
apply. If any phrase or portion of this Ordinance is held invalid or unconstitutional by any court
of competent jurisdiction, such portion shall be deemed a separate, distinct and independent
provision and such holding shall not affect the validity of the remaining portion.
SECTION FIVE: INCLUSION IN THE COLLIER COUNTY LAND DEVELOPMENT
CODE
The provisions of this Ordinance shall become and be made a part of the Land
Development Code of Collier County, Florida. The sections of the Ordinance may be
renumbered or re-lettered to accomplish such, and the word "ordinance" may be changed to
"section," "article," or any other appropriate word.
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SECTION SIX: EFFECTIVE DATE
This Ordinance shall become effective upon filing with the Florida Department of State.
PASSED AND DULY ADOPTED by the Board of County Commissioners of Collier
County, Florida, this 11th day of April, 2017.
ATTEST: BOARD OF COUNTY COMMISSIONERS
DWIGHT E. BROCK, CLERK OF COLLIER COUNTY, FLORIDA
By:__________________________ By:_____________________________
, Deputy Clerk PENNY TAYLOR, Chairman
Approved as to form and legality:
__________________________
Scott A. Stone
Assistant County Attorney
04-CMD-01077/____ (3/29/17)
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