1. 1.
   Floodplain Overlay District (FP-O). This overlay district is intended to comprise those certain areas of the city subject to periodic inundation and flooding which may result in loss of life and property, health and safety hazards, disruption of business and governmental services, extraordinary public expense for flood protection and relief, and impairment of the tax base, all of which adversely affect the public health, safety and general welfare of the public; and
2. 2.
   Causes of Flooding. Flood losses are caused by the cumulative effect of obstructions in flood hazard areas which increase flood heights and velocities, and by the occupancy of flood hazard areas by uses vulnerable to floods and therefore hazardous to other lands because they are inadequately elevated, floodproofed, or otherwise protected from flood damage.

1. 1.
   Investigation. Conduct investigations and surveys to determine compliance or noncompliance with these regulations. Incidental to such investigations and surveys, the Floodplain Administrator may, with the consent of the landowner or the person entitled to possession of the premises, or as may be authorized by law, enter into and upon any land or structure to be inspected and examined. Additionally, the right of entry and inspection may be obtained by the Floodplain Administrator by application to and proper orders or warrants issued from a court of proper jurisdiction.
2. 2.
   Orders. Issue written orders requiring compliance with these regulations. Such orders shall be served personally or by registered or certified mail upon the person deemed to be violating these regulations; provided, however, that if such person is not the owner of the land or structure in which the violation is deemed to exist or have occurred, a copy of such order shall be sent by registered or certified mail to the owner of such land or structure. The date of the mailing shall be deemed the date of service of any order served by registered or certified mail.
3. 3.
   Actions. Initiate steps necessary for the enforcement of these regulations.

Interpretation. In the interpretation and application of these regulations, the provisions of this Article shall be held to be the minimum requirements necessary and shall be liberally construed for the promotion of the public's health, safety, and general welfare. 

Amendments. Amendments to these regulations may be proposed by motion of the Council, the City Manager, by the request of any person, or by recommendation of the Commission. Amendments to the Official Zoning Map, which specifically includes initial zoning of newly annexed territory or rezoning of any parcel within the city, shall be proposed by the owner, purchaser, or a designated agent, or by the Council or the Floodplain Administrator. 

1. 1.
   Duties and Responsibilities of the Floodplain Administrator. Section 10-9-1.8, Floodplain Administrator;
2. 2.
   Variances. Section 10-9-9.3, Floodplain Variance;
3. 3.
   Administrative Review Procedures. Section 10-9-6.4, Floodplain Development Permit; and
4. 4.
   Administrative Appeals. Section 10-9-9.2, Appeal of Administrative Decision.

1. 1.
   FIRMs. Floodplains and special flood hazard areas are identified by FEMA in a scientific report entitled, "The Flood Insurance Study For Arapahoe County And Incorporated Areas", dated April 11, 2024, and accompanying flood insurance rate maps (FIRMs). This report and any subsequent amendments to this report are hereby adopted and declared to be a part of these regulations by this reference. The flood insurance study (FIS) and FIRMs are on file and are available for public inspection during regular business hours at the following locations:

   1. a.
      Public Works. Engineering and Utilities Division, Public Works Department, Littleton Center, 2255 West Berry Avenue, Littleton, Colorado; and 
   2. b.
      Library. Bemis Public Library, 6014 South Datura Street, Littleton, Colorado.
2. 2.
   FHADs. Flood Hazard Area Delineation (FHAD) studies produced by the Mile High Flood District, as may be amended and updated, hereby adopted by reference as part of these regulations when adopted by Mile High Flood District and Colorado Water Conservation Board, and subsequently by the Council.
3. 3.
   Other Sources. Other sources, such as CLOMRs, LOMRs, preliminary FIRMs and FISs, drainage studies, Site Plans, or Master Development Plans, as determined by the Floodplain Administrator, adopted by the Council, and accepted by local, regional, state, or federal agencies having jurisdiction.
4. 4.
   Areas Removed from the SFHA by Fill. These areas are identified by FEMA by the issuance of a letter of map revision based on fill (LOMR-F). For purposes of the Floodplain Regulations, this includes all existing and proposed LOMR-F areas, if the LOMR-F area has not previously been superseded by a standard LOMR.
5. 5.
   Base Flood Elevation Data. When base flood elevation data has not been provided in accordance with the foregoing paragraphs or an area has been designated Zone A on the FIRM, the Floodplain Administrator shall obtain, review, and reasonably utilize any base flood elevation data available from federal, state, or other sources in order to administer the applicable conditions of the Floodplain Regulations. If adequate data is not available, the Floodplain Administrator shall require the applicant to provide hydraulic analysis, additional data, survey data, other information, and/or studies for review.
6. 6.
   Most Restrictive Data. In cases where there are multiple studies or conflicting base flood elevation data, the data which is most restrictive in limiting impacts to floodplains and special flood hazard areas and which restricts development will be used.

1. 1.
   Minimum Required. Considered as minimum requirements;
2. 2.
   Favoring Governing Body. Liberally construed in favor of the governing body; and
3. 3.
   Nonlimiting. Deemed neither to limit nor repeal any other powers granted under state statutes.

1. 1.

   Protect human life and health;

2. 2.

   Minimize expenditures of public money for costly flood control projects;

3. 3.

   Minimize the need for post-flood rescue and relief efforts which are, generally, undertaken at public expense;

4. 4.

   Minimize prolonged business interruptions;

5. 5.

   Minimize damage to critical facilities, infrastructure, and other public facilities which are located in floodplains, such as water, sewer, and gas mains; electric and communications stations; and streets and bridges;

6. 6.

   Maintain a stable tax base by providing for the sound use and development of floodplains that have minimum flood damage potential and in such a manner as to minimize future flood blight areas;

7. 7.

   Ensure that information is available to potential buyers that property is in a floodplain; and

8. 8.

   Ensure that those who occupy floodplains are aware of the risk and assume responsibility for their actions.

1. 1.
   Restrict or prohibit uses which are dangerous to health, safety, and property due to flooding or erosion hazards or which cause greater flood heights and velocities;
2. 2.
   Require that uses and associated facilities which are vulnerable to floods are adequately protected against flood damage at the time of initial construction;
3. 3.
   Control alteration of natural floodplains, stream channels, and natural protective barriers that convey or confine floodwaters;
4. 4.
   Control filling, grading, dredging, and other development which may increase flood damage;
5. 5.
   Prevent or regulate the construction of barriers in floodplains that will unnaturally divert floodwaters or which may increase flood hazards in other areas;
6. 6.
   Limit new construction or installation of residential or non-residential structures in floodplains or special flood hazard areas;
7. 7.
   Restrict encroachments, including fill, new construction, and other development in any floodplain or special flood hazard area unless a technical evaluation demonstrates that the encroachments will not result in an increase in flood elevations more than six inches during the occurrence of the base flood, or a FEMA-approved Conditional Letter of Map Revision (CLOMR) is provided;
8. 8.
   Require minimum clearance or freeboard of one foot, between the 100-year base flood elevation and a structure’s lowest floor (including basement) and applicable facilities which may be impacted by or adjacent to the base flood; and
9. 9.
   Consider cases where protection should be given from flooding in excess of the 100-year storm event, including access routes critical to the protection of the public health, safety, and welfare, or where flooding in excess of the 100-year storm event could result in loss of life, significant damage to utilities and infrastructure, or result in hazardous materials being transported in floodwaters.

1. 1.
   Impacts. If a development or construction project is within the floodplain but outside of the FEMA regulatory floodway, the Administrator may require a hydraulic analysis to verify floodplain impacts to surrounding properties, at their discretion.
2. 2.
   Prohibited Unless CLOMR. Any proposed development or construction within a FEMA floodplain where a regulatory floodway is not defined, which causes an increase in existing conditions model one percent chance flood water surface elevations over six inches is prohibited, unless approved by a Commission public hearing and a Conditional Letter of Map Revision (CLOMR) is approved by FEMA prior to start of construction. If the project is not within a FEMA floodplain, then a proposed increase over six inches in one percent chance flood elevations must be approved by the Administrator, Commission public hearing, and Mile High Flood District prior to construction.
3. 3.
   Hydraulic Analysis.​

   1. a.
      If proposed development or construction is within a floodplain where base flood elevations are not defined, the Administrator will require a hydraulic analysis as described in Section 10-7-1.3, Applicability, Compliance, and Interpretation.
   2. b.
      If the development maintains equivalent effective conveyance (compensating fill with cut in a given hydraulic cross-section that does not raise the channel invert), a hydraulic analysis may not be required at the discretion of the Administrator.
   3. c.
      The Administrator has the discretion to require a FEMA review and approved CLOMR prior to construction to confirm hydraulic analysis results.
   4. d.
      All hydraulic analyses must be performed and certified by a registered professional engineer in Colorado competent in open channel hydraulics.
4. 4.
   ​Prohibited Increase in BFE. Any proposed development or construction that causes an increase (i.e., greater than 0.00 feet) in base flood elevations on an insurable structure, established either by independent study or by published FEMA base flood elevations, is prohibited. Such condition also applies to projects in the flood fringe outside of a regulatory floodway.
5. 5.
   Infill Projects. Significant fill projects (over one-quarter acre in surface area and elevated above the one percent chance flood elevation) that concentrate floodwaters and increase the one percent chance flood depth (in feet) and velocity (feet per second) such that the multiplicative product of average velocity and average depth increases and its value is equal to or greater than 7.0 (ft²/second), and such one percent chance floodwaters are not entirely contained within a drainage-dedicated easement or tract, are prohibited. Such conditions also apply to areas of flood fringe outside a regulatory floodway. 
6. 6.
   Support or No Support. If the development does not maintain equivalent flood fringe and floodway volumes, the Administrator may not support the proposal.

1. 1.
   New Construction and Substantial Improvements. All new construction and substantial improvements shall be: 

   1. a.
      Designed or modified and adequately anchored to prevent flotation, collapse, or lateral movement, and shall resist the hydrostatic and hydrodynamic loads of floods, including effects of buoyancy. 
   2. b.
      Constructed by accepted methods and practices that minimize flood damage.
   3. c.
      Constructed with materials resistant to flood damage. 
   4. d.
      Constructed with electrical, heating, ventilation, plumbing, and air conditioning equipment, and other service facilities which are elevated a minimum of one foot above the base flood elevation and designed to prevent water from entering into or accumulating within the components during conditions of flooding.
2. 2.
   Manufactured Homes. All manufactured homes shall be installed using methods and practices that minimize flood damage. Manufactured homes and their supporting utilities shall be elevated a minimum of one foot above the base flood elevation and anchored to resist flotation, collapse, or lateral movement, and the hydrostatic and hydrodynamic loads of floods. This requirement is in addition to state and local anchoring requirements for wind forces.
3. 3.
   New Utilities. All new utilities shall follow these requirements: 

   1. a.

      Water supply systems shall be designed to minimize or eliminate infiltration of floodwaters;

   2. b.

      Sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems, and to prohibit discharges from the systems into floodwaters; and

   3. c.

      On-site waste disposal systems shall be located to avoid being damaged, or from releasing contaminants, during flooding.

4. 4.
   Freeboard. A minimum vertical clearance of one foot shall be provided between the floodplain elevations and the lowest floor (including basement) of all new or substantially improved structures within or immediately adjacent to the floodplain, and other applicable facilities which may be impacted by the floodplain freeboard is required to allow for uncertainty in the floodplain modeling, changes to the drainageway, and to provide an additional factor of safety for structures and facilities which would experience damages or hazards during inundation.

1. 1.

   Shall be designed in a manner consistent with the flood protection objectives of these regulations;

2. 2.

   Shall have utility systems and facilities located and designed to minimize flood damage potential;

3. 3.

   Shall meet the requirements of the most recent version of the SDDTC; and

4. 4.
   Base flood elevation data shall be provided for all lots within, and immediately adjacent to, the floodplain.
5. 5.
   In the case of a FEMA CLOMR or LOMR, a plat restriction shall prohibit the issuance of Building Permits on the affected lots until a map revision has been deemed effective by FEMA or a similar map change process has been approved by the city for non-FEMA mapped floodplains.

1. 1.
   The lowest floor (including basement) shall be elevated to one foot above the base flood elevation; 
2. 2.
   Within FEMA zones A, AO, AH, or other areas of designated shallow flooding, the lowest floor (including basement), shall be elevated one foot above the highest adjacent grade, or the base flood elevation, or to the depth number specified on the FIRM, whichever is greater. Three feet of freeboard shall be provided if no depth number is specified.
3. 3.
   Within areas of potential shallow flooding, on-site drainage shall be directed around and away from structures.
4. 4.
   On property removed from the floodplain by issuance of a FEMA letter of map revision based on fill (LOMR-F), structures shall meet these standards.
5. 5.
   This Section applies to the entire structure for substantial improvement or substantial damage repair within the floodplain. 
6. 6.
   Upon completion of the construction of the structure, a professional engineer registered in the State of Colorado shall certify that all requirements listed above are met in the form of an elevation certificate, and submitted to the Administrator. 

1. 1.
   The lowest floor (including basement) shall be elevated to one foot above the level of the base flood elevation; or, together with utility and sanitary services, shall: 

   1. a.
      Be floodproofed below an elevation one foot above the base flood elevation with substantially watertight walls; and
   2. b.
      Have structural components which withstand hydrostatic and hydrodynamic loads of flood flows and the effects of buoyancy.
2. 2.
   Within zones A, AO, AH, or other areas of designated shallow flooding, the lowest floor (including basement) shall be elevated one foot above the highest adjacent grade, or the base flood elevation, or to the depth number specified on the FIRM, whichever is greater; or, together with utility and sanitary services, shall be floodproofed below an elevation one foot above the base flood elevation, or to the depth number specified on the FIRM, whichever is greater, with substantially watertight walls. If a depth number is not specified, the minimum freeboard shall be three feet from the highest adjacent grade.
3. 3.
   This Section applies to the entire structure for substantial improvements or substantial damage repair within the floodplain. 
4. 4.
   Within areas of potential shallow flooding, on-site drainage shall be directed around and away from existing and proposed structures. 
5. 5.
   Upon completion of the construction of the structure, a professional engineer registered in the State of Colorado shall certify that all requirements listed above are met in the form of an elevation certificate, and submitted to the Administrator.

1. 1.
   All manufactured homes that are placed or substantially improved in or adjacent to the floodplain on sites located inside or outside of an existing manufactured home park or subdivision, in a new manufactured home park or subdivision, in an expansion to an existing manufactured home park or subdivision, or in an existing manufactured home park or subdivision where the manufactured home has suffered substantial damage as a result of a flood, shall be elevated on a permanent foundation such that the lowest floor and electrical, heating, ventilation, plumbing, and air conditioning equipment, and other service facilities including ductwork, are elevated to one foot above the base flood elevation and securely anchored to adequately anchored foundation system to resist flotation, collapse, and lateral movement. 
2. 2.

   All manufactured homes in the floodplain shall be anchored in accordance with one or more of the following requirements:

   1. a.

      Over the top ties at each of the four corners of each unit; for units greater than 50 feet long, two additional ties per side at intermediate locations; and for units less than fifty 50 feet long, one additional tie per side.

   2. b.

      Frame ties at each corner of each unit; for units greater than 50 feet long, five additional ties per side at intermediate points; for units less than 50 feet long, four additional ties per side.

   3. c.

      Each component of the anchoring system shall be capable of sustaining a force of 4,800 pounds.

   4. d.

      Any additions to a manufactured home shall be similarly anchored.

1. 1.
   Grading and placement of fill material on a site located within a floodplain is permitted only upon approval of a Floodplain Development Permit and based upon findings that: 

   1. a.
      Requirements of Section 10-7-1.4, Purposes and Safeguards; ARTICLE 10-7-2, Floodway Regulations; and of this Article are met, as applicable.
   2. b.
      Placement of fill material in a floodplain shall not adversely affect the efficiency of the watercourse to convey storm runoff.
   3. c.
      The amount of fill material to be deposited shall only be the minimum necessary to achieve the required floodproofing of structures.
   4. d.
      No fill materials are being placed in any floodway.
   5. e.
      Fill materials shall be adequately protected against erosion by strong vegetative cover, riprap, or bulkheads.
   6. f.
      A determination that the fill will not result in increased flood heights, additional threats to public safety, extraordinary public expense, create nuisances, or conflict with other existing local laws or ordinances. 
2. 2.
   New structures proposed for construction in areas removed from the floodplain by fill by issuance of a FEMA letter map revision by fill (LOMR-F) must comply with the requirements of Paragraph G, Residential Construction Standards, and Paragraph H, Non-Residential Construction Standards, above.

1. 1.
   Be on a site for fewer than 180 days;
2. 2.

   Be fully licensed and ready for highway use. A recreational vehicle is ready for highway use if it is on its wheels, is attached to the site only by quick disconnect type utilities and security devices, and has no permanently attached structures; or 

3. 3.

   Meet the elevation and anchoring requirements for manufactured homes in Paragraph J, Construction Standards for Manufactured Homes, above.

1. 1.
   Channelization and flow diversion projects shall analyze the sediment transport, erosion, deposition, and channel migration, and properly mitigate potential problems through the project as well as upstream and downstream of any improvement activity. Dependent on the complexity of the project and material to be encountered, a detailed analysis of sediment transport and overall channel stability may be required to assist in determining the design. 
2. 2.
   Channelization and flow diversion projects shall evaluate the residual 100-year floodplain. 
3. 3.
   Any channelization or other stream alteration activity proposed by an applicant must be evaluated for its impact on the regulatory floodplain and be in compliance with all applicable federal, state, and local floodplain rules, regulations, and ordinances. 
4. 4.
   Any alteration of a watercourse shall be designed and sealed by a registered Colorado professional engineer. 
5. 5.
   All activities within the floodplain shall meet all applicable federal, state, and city floodplain requirements and regulations. Discharges of dredged or fill material into a watercourse may require prior issuance of a permit by the U.S. Army Corps of Engineers pursuant to Section 404 of the Clean Water Act (33 USC 1344).
6. 6.
   Within the regulatory floodway, stream alteration activities shall meet the requirements of this Section.
7. 7.
   Maintenance shall be required for any altered or relocated portions of watercourses so that the flood-carrying capacity is not diminished. 
8. 8.
   Notification of adjacent local governments, Colorado Water Conservation Board, and Mile High Flood District.
9. 9.
   Prior to any alteration or relocation of a watercourse, the applicant must submit evidence of such notice to FEMA.
10. 10.
    This notice must certify that the flood-carrying capacity within the altered or relocated portion of the watercourse has been and will be maintained. 

1. 1.
   Open fences are permitted in the floodplain without a Floodplain Development Permit. 
2. 2.
   Chain-link or other similar small opening or narrow gap fencing materials are considered a solid fence for the purpose of this regulation due to the potential for debris accumulation. 
3. 3.
   A solid fence that may impact the flood-carrying capacity of the floodplain as determined by the Administrator, will require a Floodplain Development Permit in order to evaluate impacts.
4. 4.
   All fence construction, including replacement of existing fences, shall comply with this Section.

1. 1.
   Classification. Critical facilities are classified under the following categories:

   1. a.
      Essential services consisting of:

      1. 1.

         Public safety (police stations, fire and rescue stations, emergency vehicle and equipment storage, and emergency operation centers);

      2. 2.

         Emergency medical (hospitals, ambulance service centers, urgent care centers having emergency treatment functions, and non-ambulatory surgical structures, but excluding clinics, doctor's offices, and non-urgent care medical structures that do not provide these functions);

      3. 3.

         Designated emergency shelters;

      4. 4.

         Communications (main hubs for telephone, broadcasting equipment for cable systems, satellite dish systems, cellular systems, television, radio, and other emergency warning systems, but excluding towers, poles, lines, cables, and conduits);

      5. 5.

         Public utility plant facilities for generation and distribution (hubs, treatment plants, substations and pumping stations for water, power, and gas, but not including towers, poles, power lines, buried pipelines, transmission lines, distribution lines, and service lines);

      6. 6.

         Air transportation lifelines (airports municipal and larger, helicopter pads and structures serving emergency functions, and associated infrastructure (aviation control towers, air traffic control centers, and emergency equipment aircraft hangars);

      7. 7.

         Exemptions to this category include wastewater treatment plants, non-potable water treatment and distribution systems, and hydroelectric power generating plants, and related appurtenances; and

      8. 8.

         Public utility plant facilities may be exempted if it can be demonstrated to the satisfaction of the Floodplain Administrator that the facility is an element of a redundant system for which service will not be interrupted during a flood. At a minimum, it shall be demonstrated that redundant facilities are available (either owned by the same utility or available through an intergovernmental agreement or other contracts) and connected, the alternative facilities are either located outside of the floodplain or are compliant with the provisions of these floodplain regulations, and an operations plan is in effect that states how redundant systems will provide service to the affected area in the event of a flood. Evidence of ongoing redundancy shall be provided to the Floodplain Administrator on an as-needed basis upon request.

   2. b.

      Hazardous materials facilities including facilities that produce or store highly volatile, flammable, explosive, toxic, and/or water-reactive materials including:

      1. 1.

         Chemical and pharmaceutical plants and manufacturing;

      2. 2.

         Laboratories containing highly volatile, flammable, explosive, toxic, and/or water-reactive materials;

      3. 3.

         Refineries;

      4. 4.

         Hazardous waste storage and disposal sites; and

      5. 5.

         Aboveground gasoline or propane storage or sales centers.

   3. c.

      Facilities shall be determined to be critical facilities if they produce or store materials in excess of threshold limits. If the owner of a facility is required by the occupational safety and health administration (OSHA) to keep a material safety data sheet (MSDS) on file for any chemicals stored or used in the workplace, and the chemicals are stored in quantities equal to or greater than the threshold planning quantity (TPQ) for that chemical, then that facility shall be considered to be a critical facility. The TPQ for these chemicals is either 500 pounds or the TPQ listed (whichever is lower) for the 356 chemicals listed under 40 CFR section 302 (2010), also known as extremely hazardous substance; or 10,000 pounds for any other chemical. This threshold is consistent with the requirements for responsible chemicals established by the Colorado Department of Public Health and Environment. OSHA requirements for MSDS can be found in 29 CFR section 1910 (2010). The environmental protection agency (EPA) regulation "designation, reportable quantities, and notification" 40 CFR section 302 (2010) and OSHA regulation "occupational safety and health standards" 29 CFR section 1910 (2010) are incorporated herein by reference and include the regulations in existence at the time of the promulgation of this Subsection, but exclude later amendments to or editions of the regulations. Specific exemptions to this category include:

      1. 1.

         Finished consumer products within retail centers and households containing hazardous materials intended for household use, and agricultural products intended for agricultural use;

      2. 2.

         Buildings and other structures containing hazardous materials for which it can be demonstrated to the satisfaction of the Floodplain Administrator by hazard assessment and certification by a qualified professional that a release of the subject hazardous material does not pose a major threat to the public; and

      3. 3.

         Pharmaceutical sales, use, storage, and distribution centers that do not manufacture pharmaceutical products.

      4. 4.

         These exemptions shall not apply to buildings or other structures that also function as critical facilities under another category outlined in this subsection.

   4. d.

      At-risk population facilities include medical care, congregate care, and schools consisting of:

      1. 1.

         Eldercare (nursing homes);

      2. 2.

         Congregate care serving 12 or more individuals (daycare and assisted living); and

      3. 3.

         Public and private schools (preschools, K - 12 schools) and before-school and after-school care serving 12 or more children.

   5. e.
      Facilities vital to restoring normal services including government operations consisting of:

      1. 1.
         Essential government operations (public records, courts, jails, building permitting and inspection services, community administration and management, maintenance and equipment centers);
      2. 2.
         Essential structures for public colleges and universities (dormitories, offices, and classrooms only).
      3. 3.

         Facilities may be also exempted if it is demonstrated to the Administrator that the facility is an element of a redundant system for which service will not be interrupted during a flood. At a minimum, it shall be demonstrated that redundant facilities are available (either owned by the same entity or available through an intergovernmental agreement or other contracts), the alternative facilities are either located outside of the floodplain or are compliant with this subsection, and an operations plan is in effect that states how redundant facilities will provide service to the affected area in the event of a flood. Evidence of ongoing redundancy shall be provided to the Administrator on an as-needed basis upon request

2. 2.
   Protection for Critical Facilities. All new and substantially improved critical facilities and new additions to critical facilities located within the area of special flood hazard or other flood areas shall be regulated to a higher standard than structures not determined to be critical facilities. For the purposes of these regulations, protection shall include one of the following: 

   1. a.

      Location outside the area of special flood hazard or other flood areas, or

   2. b.

      Elevation or floodproofing of the structure to at least two feet above the base flood elevation, or elevation at or above the two-tenths percent (0.2%) annual chance flood elevation, where designated, whichever is greater.

3. 3.
   Ingress and Egress for New Critical Facilities. New critical facilities shall, when practical as determined by the Floodplain Administrator, have continuous non-inundated access (ingress and egress for evacuation and emergency services) during a base flood event. 

1. 1.
   Construction in the Floodway. Construction of new buildings or substantial improvements to existing structures, residential or non-residential, are prohibited in the floodway.
2. 2.
   Makeshift Structures and Shelters. Tents and makeshift structures, enclosures, or other shelters used for human habitation are prohibited in the floodway.
3. 3.
   Increase in Base Flood Elevation. Development or construction that causes an increase in the base flood elevation on any insurable structure is prohibited.
4. 4.
   Waste Disposal Facilities. Solid waste disposal facilities (including, but not limited to, junkyards, sanitary landfills, and automobile wrecking yards) are prohibited in the floodway.
5. 5.
   Outdoor Storage. Outdoor storage of any material is prohibited in the floodway.
6. 6.
   Watercourse Capacity. No use shall affect the efficiency or restrict the capacity of any watercourse, drainage ditch, or any other drainage facility or system.

Encroachments. Encroachments, including fill or other development not listed above, are prohibited unless it has been demonstrated through hydrological and hydraulic analyses prepared by a registered Colorado professional engineer, that there is no increase (0.00’) in flood elevations during the occurrence of the base flood discharge (No Rise Certification), approval by a Commission public hearing, and FEMA approval of a CLOMR with floodway revision.

Encroachment Exceptions. Encroachments may be permitted in the floodway, at the discretion of the Administrator, when the activity is strictly drainageway maintenance in which the intent is to restore the natural conditions or hydraulic capacity of the drainageway provided that the activity does not cause more than a 0.00-foot rise compared to effective conditions BFEs and that any BFE rise compared to existing conditions is contained entirely within public property which would not otherwise require adverse impact notification.

1. 1.
   Agriculture. Agricultural uses including general farming; raising of plants, flowers, sod, and nursery stock; and grazing of livestock. No use shall include the construction of any new structures, the alteration of any existing structures, or solid fencing.
2. 2.
   Recreational Uses. Public and private recreational uses including play fields, golf courses, driving ranges, picnic grounds, fishing areas, and recreational trails. No use shall include the construction of any new structures, the alteration of any existing structures, or solid fencing.
3. 3.
   Residential Accessory Use. Lawns, gardens, and similar uses accessory to the residential use of the land.

State and Federal Regulations. All uses shall comply with applicable state and federal regulations related to environmental protection, including those pertaining to air or water pollution.

Measurements. Accurate and representative measurements, as necessary, shall be made according to accepted engineering practice. Measurements shall be made at or anywhere outside the property lines of the property from which any emission is generated.

1. 1.

   All Materials. All materials shall be stored and all grounds maintained in a manner that will not attract or aid the propagation of insects or rodents or create a health hazard.

2. 2.

   Outdoor Storage. No outdoor storage of materials and equipment shall be permitted unless contained by a site-obscuring fence or landscaped screening, as set out in Section 10-1-1.4, Land Use Standards.

3. 3.

   Hazardous Materials. Developments that store hazardous materials must comply with state standards and the federal standards, 40 CFR Part 262 and 264, and shall demonstrate such compliance. All hazardous materials must be stored above ground. Transport of and disposal of such materials shall be in conformance with all applicable local, state, and federal regulations with such compliance demonstrated.

Air Pollution. Dust and other forms of air pollution borne by the wind from sources within lot boundaries, such as storage areas, yards, roads, and so forth, shall be kept to a minimum by landscaping, paving, or other acceptable means.

Electromagnetic Interference. Electromagnetic interference from any operation of any use in any district shall not adversely affect the operation of any equipment located off the lot on which such interference originates.

Discharge. Illicit discharges into the city's MS4 shall be prohibited in accordance with Title 7, Chapter 7, Littleton Storm Drainage Ordinance, of the City Code.

City Determination. If a violation can be determined by the Director or an outside agency, an inspection and determination shall be made and an order of compliance requiring correction of the violation shall be issued within 10 days. If necessary to eliminate a violation, the Director shall cause to be taken lawful action as provided for in the City Code.

Third Party Determination. If determining a violation involves the use of skilled personnel or instruments that are not available to the city, the Director shall notify the person who owns or controls the use in question.

Notice. The notice shall describe the alleged violation and state the reasons why the violation exists. The notice shall require a determination of compliance or correction of the alleged violation within a time period established by the Director. The notice shall state that if the alleged violation is not corrected, a technical determination shall be made by qualified engineers or other technical consultants and that if an alleged violation is found, enforcement action shall be taken according to Code.

Liability.  The violator shall be responsible for the payment of all costs of such inspection and determination.