Solano County Municipal Code Art. IV Building Permits, New Construction, Additions, and Replacement Structures

Any person proposing to develop any property utilizing an on-site sewage disposal system, whether for new construction, remodel, addition or replacement, must submit to the Environmental Health Services Division two (2) copies of the general site layout, of the detailed on-site sewage disposal plan drawn to scale (1:20 or 1:30), and of the floor plan for the proposed development. The plans must be complete, and must clearly show the exact locations of the following whether existing or proposed:

(a) Parcel number and location address, if assigned,

(b) Name, address, and phone number of property owner, contact person, and person preparing plans,

(c) Vicinity map,

(d) Scale used,

(e) Lot dimensions, including all property lines,

(f) Setbacks and side-yards,

(g) Paved areas and unpaved areas subject to vehicular traffic,

(h) Easements and rights-of-way, public and private,

(i) Structures, dwellings (including pools and auxiliary buildings),

(j) Animal enclosures,

(k) Fuel tanks, hazardous material storage,

(l) Plumbing stub-out,

(m) Water lines (public and private),

(n) Areas subject to flooding, inundation, storm water overflow, or ten-year storm event,

(o) Existing and proposed wells, abandoned wells, springs, neighboring wells, streams, ditches, canals, culverts, ponds, lakes, swales, 10-year flood plains, or any body of water (intermittent or perennial) located within 100 feet of property lines,

(p) Existing and proposed on-site sewage disposal systems (including replacement areas), abandoned septic tanks, pretreatment and storage devices, sewer lines, storm sewers,

(q) Soil profile test holes, percolation test holes, groundwater observation wells,

(r) Percent and direction of slope in absorption system area and 50 feet adjacent to it on all sides. A contour map is recommended and may be required by the Environmental Health Services Division depending on conditions observed at the site,

(s) Trees within 10 feet of sewage disposal areas (including replacement areas),

(t) Underground utilities within 10 feet of septic system (including replacement area),

(u) Cut banks, unstable land forms, bluffs and ravines,

(v) Written information required to determine availability of public sewer (see Section 6.4-20),

(w) Floor plan (including number of bedrooms).

(Ord. No. 1609, §18)

Each proposed project shall be required to have a site evaluation as indicated in Article VIII, Sections 6.4-81, 6.4-81.1, and 6.4-81.2 for on-site sewage disposal systems. Exception: Unless indicated otherwise in this Chapter, projects that do not by themselves cause any increase in the potential generation of sewage, and where inspection by the Environmental Health Services Division verifies the project will not significantly impact initial or replacement area for the on-site sewage disposal system do not require site evaluation as indicated in Article VIII, Sections 6.4-81, 6.4-81.1, or 6.4-81.2.

(Ord. No. 1609, §18)

(a) For new construction that generates liquid waste and for which public sewer is not available, an on-site sewage disposal system complying with these standards shall be required.

(b) For additions or remodels that increase the projected or actual wastewater flow, including bedroom additions, increases in seating capacity, or changes in business use or occupancy, the existing on-site sewage disposal system shall be evaluated and,

(1) If currently permitted by the Environmental Health Services Division and is in good condition and operating properly, it must be modified and enlarged to accommodate the projected increase. This includes, but is not limited to, providing a larger septic tank, pretreatment device, and/or enlarging or replacing the disposal field. Any modifications to the on-site sewage disposal system shall comply with these standards, except that a one time only expansion of the existing sewage disposal system to accommodate a one bedroom addition may be allowed under the following conditions:

(A) A site evaluation demonstrates a minimum of 5 feet separation exists between the bottom of the sewage disposal system and seasonal high groundwater and the septic tank is sized or is upgraded to meet the size requirements of this code. The additional field required shall be based on the proportion of additional flow, or

(B) A site evaluation demonstrates 3 to 5 feet separation exits between the bottom of the sewage disposal system and seasonal high groundwater, the septic tank is sized or is upgraded to meet the size requirements of this code and, if gravity flow is being used, a pretreatment devise is installed. The additional field required shall be based on the proportion of additional flow.

In all cases, a replacement area complying to current standards must be demonstrated, or

(2) If currently permitted by the Environmental Health Services Division and not in good condition or operating properly and cannot be corrected through minor repair of the system or replacement of tanks to be in conformance with provisions of 6.4-42(b)(1), then a new on-site sewage disposal system complying with these standards, including those for replacement area, must be provided, or

(3) If not currently permitted by the Environmental Health Services Division and does not comply with these standards then an on-site sewage disposal system complying with these standards, including those for replacement area must be provided.

(c) For additions or remodels that will not increase the projected wastewater flow but which will result in the reconstruction of or an addition to greater than 50% of the existing habitable floor space, an evaluation of the existing on-site sewage disposal system shall be required. The evaluation must include the location, condition and performance of all components of the on- site sewage disposal system and demonstrate that the system will function properly and not create a potential health, safety, or contamination hazard year round. Based upon the findings a site evaluation in conformance with Article VIII, sections 6.4-81, 6.4-81.1, and 6.4-81.2 of these standards may be required. On-site sewage disposal systems not in conformance with these standards at the time of application for the building permit shall be modified or enlarged consistent with the intent of these standards. This may include, but is not limited to, providing a larger septic tank, pretreatment device, and/or enlarging or replacing the disposal field.

(d) For building additions that encroach upon the existing disposal system or replacement area of a septic system otherwise meeting the requirements for new on-site sewage disposal systems detailed in these standards, only the impacted portion of the existing disposal system or replacement area shall be replaced.

(Ord. No. 1609, §18; Ord. No. 1655, §4)

(a) The size of the area to be used to install and replace an on-site sewage disposal system shall be based on site evaluations and the requirements listed in section 6.4-87.

(b) The area shall contain sufficient room for a 100% replacement area for the on-site sewage disposal system sized to accommodate all existing and proposed structures. The replacement area shall meet all requirements for new on-site sewage disposal systems. The replacement area required shall be based on all proposed and existing structures, site and soil evaluation, and the sizing criteria outlined in section 6.4-87.

(c) The area shall meet all requirements of this Chapter.

(d) No further improvement of a lot shall be approved if the improvement will impact any existing on-site sewage disposal system, including replacement area, in a manner that cannot be corrected in conformance with this Chapter, or if any required new or expanded septic system, and replacement area, cannot be installed in accordance with these standards.

(Ord. No. 1609, §18)

(a) Replacement structures, including, but not limited to, single family residences and companion living units, may connect into an existing on-site sewage disposal system provided the following criteria can be met:

(1) The location of the replacement structure does not encroach upon the existing on-site sewage disposal system or replacement area;

(2) The replacement structure does not have the potential to generate more sewage then the previous structure; and

(3) The system was functioning properly before removal of the previous structure, and will continue to do so in all likelihood and will not pose a threat to public health or water quality.

(4) And either condition I or II below is met

Condition I: The existing on-site sewage disposal system is permitted by the Environmental Health Services Division and complies with the requirements of these standards, including those for replacement area.

Condition II: The existing on-site sewage disposal system is permitted by the Environmental Health Services Division but does not comply with the requirements of these standards provided that a replacement area sufficient to completely replace the disposal field to current standards can be demonstrated.

(b) If section 6.4-44(a) cannot be met, then the structure shall be considered new construction and may not connect into the existing on-site sewage disposal system. A new on-site sewage disposal system and replacement area complying with all provisions of these standards shall be required.

(c) Where necessary, a site evaluation may be used to verify the on-site sewage disposal system design and replacement area required for replacement structures.

(Ord. No. 1609, §18; Ord. No. 1655, §5)