The purpose of the conservation subdivision overlay district (CSD) is to preserve undisturbed natural areas within the city's expected annexation limits by allowing higher density residential development on portions of development sites via relief from the area, density and building bulk limitations of the conventional residential districts. The CSD allows the set aside of undisturbed natural areas through the site design flexibility allowed by modifications to the standards for setbacks, lot dimensions and building bulk; however, the maximum overall density(s) for the entire site allowed in the underlying zoning district(s) shall be maintained. This allows the clustering of residential lots and units on portions of sites and thus creates the option of leaving portions of sites undisturbed in their natural state. These undisturbed natural areas provide community benefits including: Aesthetics, privacy, flood control, water quality preservation, cleaner air, noise mitigation, reduced erosion and undisturbed natural wildlife habitat. The intention of the CSD is to establish a mechanism to provide the flexibility needed to respond to conditions and constraints that may be unique to specific sites and the characteristics and constraints that are inherent to residential development in general.

(Ord. No. 09-03, § 1, 1-12-09)

The conservation subdivision overlay district is intended for use with new residential development of all kinds within the conservation residential designated areas of the comprehensive community plan, and in residential areas within the city limits as a development option. The uses permitted by right or by special use exception in an underlying zoning district may be allowed in the CSD subject to the governing ordinance passed by the board of aldermen. The development patterns and land uses allowed in a CSD shall be determined based on compatibility with surrounding developments, the unique characteristics and constraints of the site and the CSD and POD regulations, and shall be specifically listed in a CSD governing ordinance that specifies all approved variations from the underlying zoning and development regulations.

Nothing in this regulation prohibits the submission of an underlying zoning district change petition in conjunction with a CSD district petition.

(Ord. No. 09-03, § 1, 1-12-09)

A CSD development shall be "density neutral" in terms of the number of dwelling units that can be created on a site. This means that the unit count (density) of a CSD plan cannot exceed the unit count (density) that would be permitted by the applicable underlying zoning and development regulations and any requirements of other agencies with jurisdiction. A "yield plan" done in accordance with these underlying regulations shall be prepared to establish the maximum number of dwelling units that a site can accommodate and therefore the maximum density that can be allowed in a CSD development.

(Ord. No. 09-03, § 1, 1-12-09)

The governing ordinance may allow reductions to minimum lot area dimensions, yard requirements and building bulk limitations in the underlying district(s) provided they do not fall below the following minimum requirements or exceed the maximum height limit.

1.

Minimum lot area (single-family detached): 5,500 square feet.

2.

Minimum lot area (single-family attached): 4,000 square feet (per unit).

3.

Minimum lot width (single-family detached): 50 feet.

4.

Minimum lot width (duplex attached): 40 feet (per unit).

5.

Minimum lot depth: 100 feet.

6.

Building height: 40 feet.

(Ord. No. 09-03, § 1, 1-12-09)

Building setbacks shall be set no less than the following in a CSD governing ordinance.

1.

Front: 25 feet when fronting a dedicated street right-of-way.

2.

Side: 8 feet, except 0 feet for common-wall construction.

3.

Rear: 25 feet.

(Ord. No. 09-03, § 1, 1-12-09)

When developing adjacent to an established neighborhood, lot sizes and dimensions, and building setbacks, heights and bulk shall be no less than 80 percent of those of the existing neighborhood patterns adjoining the perimeter of the proposed development. These development parameters may transition to smaller lots sizes and setbacks and greater building heights and bulk for lots that are interior to the district.

(Ord. No. 09-03, § 1, 1-12-09)

Parking shall be provided pursuant to the city's existing parking regulations. A reduction in the parking requirements may be allowed if the petitioner demonstrates that such a reduction furthers the overall intent and purpose of this district. Under no circumstances will the parking requirements for any residential use be reduced below those specified for single-family residential uses in the parking regulations.

Roadways and rights-of-way shall be built and/or established in accordance with minimum Ballwin standards. If the roadway serves exclusively residential uses, does not presently and cannot in the future provide through passage to other uses or developments, no on-street parking is allowed, no more than 20 dwellings are or will ever be served, the pavement is built to Ballwin's applicable pavement section standards and the fire district approves the pavement configuration, the width of a dedicated right-of-way may be reduced to 40 feet and the width of the roadway pavement may be reduced to no less than 22 feet.

(Ord. No. 09-03, § 1, 1-12-09)

Whenever possible, CSD developments shall create, provide, incorporate and when possible dedicate public vehicular and pedestrian access to adjacent neighborhoods, schools, parks, commercial and employment centers or other destinations and activity nodes.

(Ord. No. 09-03, § 1, 1-12-09)

(1)

Sidewalks are required along both sides of streets unless alternative pedestrian paths are provided and approved as a part of the approved subdivision or site development plan.

(2)

Twenty-five percent of the total area of the site shall be set aside for undisturbed natural features, habitat preservation and land conservation. No more than half (50 percent) of such set-aside space shall consist of the following:

(a)

Areas restricted from development under the codes or laws of Ballwin or other jurisdictions.

(b)

Protected flood plains, stormwater retention/detention and water quality mitigation facilities.

(3)

Properties involved in a petition shall be under the control of the petitioner at the time the CSD petition is submitted.

(4)

All open space and common areas not preserved in their natural state shall be landscaped and recorded for ownership and maintenance by a lawfully organized association of development property owner's.

(5)

The preservation, maintenance and ownership in perpetuity of open space, common ground and set aside lands in their natural state shall be accomplished by deed restriction on the instruments recording the development authorized and established via the CSD governing ordinance.

(Ord. No. 09-03, § 1, 1-12-09)

All dwellings constructed in a CSD shall comply with the following residential design guidelines:

(1)

Each residential building shall contain street-facing architectural features which provide human scale to the facade, enhance the "curb appeal", and reinforce local building forms, types and traditions. Architectural features may include, but are not limited to, bay windows, covered porches, balconies, dormers and cupolas.

(2)

All single-family homes, townhouses, and duplexes shall have a street-oriented entrance and a street facing principal window. Such dwelling units may, as an alternative, face courtyards, gardens or similar landscaped common entrance features. In these circumstances, entries and principal windows shall face those features, but a roadway presence shall also be retained through the use of wrap around front porches, architectural features and treatments and landscaping that define and enhance any and all walls facing a roadway or public space.

(3)

No garage wall shall be closer to the street than any other house wall. Garage or door openings facing a street shall not exceed 50 percent of the width of the dwelling facade.

(4)

All new construction shall include durable, high quality exterior building materials. The use of bright colors and highly reflective surfaces shall be limited to accent features only.

(5)

The quality of the exterior materials, architectural details and their application shall be consistent on all sides of all buildings.

(6)

Street trees shall be planted every 45 feet along all streets or as required by the subdivision ordinance, whichever is more restrictive.

(Ord. No. 09-03, § 1, 1-12-09)