BILL REQ. #:  H-5160.1 

     AN ACT Relating to construction standards for state construction projects; and adding a new chapter to Title 43 RCW.

BE IT ENACTED BY THE LEGISLATURE OF THE STATE OF WASHINGTON:

NEW SECTION.  Sec. 1   It is the goal of the legislature that new state construction projects or state construction projects that are considered substantial redevelopment adhere to the 65/10/0 project design standard and will not significantly harm the aquatic environment and anadromous fisheries. To meet these goals the legislature intends to do the following:
     (1) Eliminate storm water discharge to all surface waters from greenfields construction projects on all types of soil by all state agencies including but not limited to the department of transportation, the parks and recreation commission, the department of general administration, and the department of corrections;
     (2) Preserve habitat for aquatic life within a watershed with innovative construction design and development techniques; and
     (3) Foster broad community acceptance of the use of significantly less impervious surface and greater natural habitat conservation on sites.

NEW SECTION.  Sec. 2   The definitions in this section apply throughout this chapter unless the context clearly requires otherwise. However, additional definitions not included in this section are included in the department of ecology's 2005 Stormwater Management Manual for Western Washington and the Low Impact Development Technical Guidance for Puget Sound, published by the Puget Sound action team.
     (1) "Effective impervious surface" means impervious surface that is connected to surface water directly or with a conveyance device, such as a ditch or pipe.
     (2) "Forest restoration" means the process of restoring native vegetation, soils, and mulch on disturbed land with the intent of eventually achieving a forested condition. A bioretention facility designed with deeply restored soils and predominated by native vegetation may be classified as restored forest.
     (3) "Forested area" means an area characterized by the presence of undisturbed soils and vegetation cover that was likely present prior to the immigration of Europeans to the United States over substantially the entire site. If original vegetation cover is unknown, it is assumed to be a conifer forest characterized by a predominance of evergreen trees with undisturbed soils.
     (4) "Greenfields" means sites that have never been developed or sites in the process of redevelopment that will have substantially all existing structures removed.
     (5) "Hardscapes" includes impervious surfaces or pervious pavement systems.
     (6) "Overland flow" means precipitation that is collected and conveyed on the surface of the ground or in other man-made conveyance systems such as ditches and pipes. "Overland flow" does not include precipitation that falls directly on naturally occurring water bodies.
     (7) "65/10/0 project design" means a project site that, after completion, retains permanently a minimum of sixty-five percent of the site as forest or restored forest; the total impervious area is limited to ten percent; the runoff from the developed portion of the site is fully dispersed in the retained forest preserve; zero overland flow discharge is allowed from the site; has no runoff collection and conveyance systems such as ditches and pipes; and meets other engineering criteria protecting health, safety, and welfare.
     (8) "Substantial redevelopment" means any reconstruction, rehabilitation, addition, or other improvement to a structure, the total cost of which equals or exceeds fifty percent of the market value of the structure before the start of construction of the improvement.
     (9) "Total impervious area" includes the sum of areas in which water cannot penetrate such as compacted soils, impervious concrete, and impervious roof tops. Pervious pavement and vegetated rooftops do not count toward total impervious area. Rooftops where at least fifty percent of annual rainfall is harvested and used for domestic purposes may not be counted as impervious areas.
     (10) "Zero effective impervious surface" means impervious surface reduction and isolation such that no runoff is generated and traditional drainage collection systems are not necessary.

NEW SECTION.  Sec. 3   In order to accomplish the intent of this chapter, all new state construction projects or state construction projects that are considered substantial redevelopment must meet the following criteria:
     (1) Site design must conform to the 65/10/0 project design standard.
     (2) A maximum of thirty-five percent of a site proposed for development by a state agency may be developed. Of this percentage, the state construction project design may be guided but not limited by practices found in the most recent version of Low Impact Development Technical Guidance Manual for Puget Sound, published by the Puget Sound action team.
     (3) The sixty-five percent of the site that will remain in or be restored to a forested condition may not be isolated as a tract but must be integrated within the project to serve as the recipient of precipitation from hardscapes.
     (4) Soil types may not be a factor in the practicality of employing the 65/10/0 project design standard.
     (5) The state construction project may not threaten public health or safety.
     (6) Local development regulations may not impede state construction projects designed to meet design criteria set forth in this section.
     (7) The state construction project is consistent with generally accepted engineering and design criteria, except as necessary to achieve the purposes set forth in this section. The deviation from accepted engineering and design criteria may not lessen protection of life and property but rather these needs must be met in alternate ways.
     (8) The state construction project must promote one or more of the following:
     (a) An innovative site design that furthers the purposes of this section;
     (b) Increased on-site storm water retention that uses a variety of native vegetation;
     (c) The project does not allow density greater or less than what would otherwise be allowed under city or county regulations and does not allow any relaxation of the critical areas regulation; or
     (d) 65/10/0 project design requirements discharge project requirements:
     (i) To reduce impervious area, one-way roads must be employed where practical;
     (ii) Bioretention facilities must be the principal method for treating and retaining storm water; and
     (iii) On a forested site, grading of a site is not allowed except for road and walk footprints, building pads, driveways, and parking areas unless the grading is absolutely necessary for project feasability.
     (9) With the exception of state highways, all roads, shoulders, turnouts for emergency vehicles, parking stalls, driveways, and similar structures must be constructed with a wearing surface consisting of some type of approved pervious pavement, such as concrete without fines, or an interlocking concrete paver system with drainage openings to facilitate rainwater infiltration.
     (10) The lowest floor elevation of any structure must be a minimum of twenty-four inches above existing grade for ten feet in any direction.
     (11) On class C and D soils, foundations for structures must be "no-excavation" type, such as piles or pin-pile footings.
     (12) Generally, roof gutters are not permitted, except for over entryways, unless the roof gutters are a part of a cistern collection system.
     (13) Roof runoff must be either infiltrated at the roof dripline or collected in cisterns and used for domestic purposes.
     (14) The state shall provide manuals for maintenance of low-impact facilities.
     (15) All structures must be provided with fire sprinkling systems.
     (16) Noncombustible siding and roofing materials for all structures and enclosed underfloor areas are required.
     (a) Gutters and downspouts should generally be avoided, but if used must be constructed of noncombustible material;
     (b) Exterior walls of buildings or structures must be constructed with materials approved for a minimum of one-hour-rated fire-resistive construction on the exterior side or constructed with approved noncombustible materials. These materials must extend from the top of the foundation to the underside of the roof sheathing; and
     (c) Buildings or structures must have all underfloor areas enclosed to the ground, with exterior walls that meet the requirements of (b) of this subsection. However, complete enclosure may be omitted where the underside of all exposed floors and all exposed structural columns, beams, and supporting walls are protected as required for exterior one-hour-rated fire-resistive construction.

NEW SECTION.  Sec. 4   Sections 1 through 3 of this act constitute a new chapter in Title 43 RCW.