§ 18-259. Design requirements.  


Latest version.
  • (a)

    Generally. Grading, erosion control practices, sediment control practices, and waterway crossings shall meet the design criteria set forth in the most recent version of the Stormwater Management Handbook for Construction Activities, City of Houston, Harris County, and HCFCD, 2006 edition, and shall be adequate to prevent transportation of sediment from the site to the satisfaction of the city engineer.

    (b)

    Clearing and grading.

    (1)

    Clearing and grading of natural resources, such as forests, wetlands and floodplains, shall not be permitted, except when in compliance all other chapters of this Code. These standards are cumulative of other federal, state, and local jurisdictional requirements.

    (2)

    Clearing techniques that retain natural vegetation and retain natural drainage patterns, as described in the Stormwater Management Handbook for Construction Activities, City of Houston, Harris County, and HCFCD, 2006 edition, shall be used to the satisfaction of city engineer.

    (3)

    Phasing shall be required on all sites disturbing greater than 30 acres, with the size of each phase to be established at plan review and as approved by the city engineer.

    (4)

    Clearing, except that necessary to establish sediment control devices, shall not begin until all sediment control devices have been installed and have been stabilized.

    (5)

    Cut and fill slopes shall be no greater than 2:1, except as approved by the city engineer to meet other community or environmental objectives.

    (c)

    Erosion control.

    (1)

    Soil must be stabilized within five days of clearing or inactivity in construction.

    (2)

    If vegetative erosion control methods, such as seeding, have not become established within two weeks, the city engineer may require that the site be reseeded, or that a nonvegetative option be employed.

    (3)

    On steep slopes or in drainageways, special techniques that meet the design criteria outlined in the Stormwater Management Handbook for Construction Activities, City of Houston, Harris County, and HCFCD, 2006 edition, shall be used to ensure stabilization.

    (4)

    Soil stockpiles must be stabilized or covered at the end of each work-day.

    (5)

    At the close of the construction season, the entire site must be stabilized, using a heavy mulch layer, or another method that does not require germination to control erosion.

    (6)

    Techniques shall be employed to prevent the blowing of dust or sediment from the site.

    (7)

    Techniques that divert upland runoff past disturbed slopes shall be employed.

    (d)

    Sediment controls.

    (1)

    Sediment controls shall be provided in the form of settling basins or sediment traps or tanks, and perimeter controls.

    (2)

    Where possible, settling basins shall be designed in a manner that allows adaptation to provide long-term stormwater management.

    (3)

    Adjacent properties shall be protected by the use of a vegetated buffer strip, in combination with perimeter controls.

    (e)

    Waterways and watercourses.

    (1)

    When a wet watercourse must be crossed regularly during construction, a temporary stream crossing shall be provided.

    (2)

    When in-channel work is conducted, the channel shall be stabilized before, during and after work.

    (3)

    All on-site stormwater conveyance channels shall be designed according to the criteria outlined in the Stormwater Management Handbook for Construction Activities, City of Houston, Harris County, and HCFCD, 2006 edition.

    (4)

    Stabilization adequate to prevent erosion shall be provided at the outlets of all pipes and paved channels.

    (f)

    Construction site access.

    (1)

    A temporary access road shall be provided at all sites.

    (2)

    Other measures may be required at the discretion of the city engineer in order to ensure that sediment is not tracked onto public streets by construction vehicles or washed into storm drains.

(Ord. No. 2009-30, § 1(38-55), 10-19-2009)