King County
Public Rules and Regulations

Public Rules

Title: Discharge of Construction Dewatering to the Sanitary Sewer

Document Code No.: PUT 8-14 (PR)
Department/Issuing Agency: Department of Natural Resources/Industrial Waste Program
Effective Date: February 12, 1999
Approved: /s/ Ron Sims
Type of Action: Revised (reissued to incorporate agency name change due to reorganization of rule originally issued on October 1, 1995).

1.0 SUBJECT TITLE: Discharge of Construction Dewatering to the Sanitary Sewer

2.0 PURPOSE:

2.1 To establish rules governing procedures for the discharge of construction dewatering into the metropolitan sewer system.

3.0 ORGANIZATIONS AFFECTED:

3.1 Any person, as that term is defined in King County Code (K.C.C.) 28.82.600, discharging water to the sanitary sewer resulting from construction dewatering.

3.2 King County Department of Natural Resources; Wastewater Treatment Division; Water and Land Resources Division; Industrial Waste Program.

4.0 REFERENCES:

4.1 K.C.C. 28.84.060 D.5.K. - Discharge Standards and Limitations (Specific Prohibitions for Discharges of Clean Water).

4.2 King County Ordinance No. 11034 - Establishes the Fees, Rules, and Regulations for the Disposal of Industrial Wastes into the Metropolitan Sewerage System.

5.0 DEFINITIONS:

5.1 "Construction Dewatering" shall mean the act of pumping ground water or storm water away from an active construction site.

5.2 "Dry season" shall mean that period of time from May through October of each year.

5.3 "Ground water" shall mean water in a saturated zone or stratum beneath the surface of land or below a surface water body.

5.4 "Storm water" shall mean water originating from rainfall and other precipitation that is found in drainage facilities, rivers, streams, springs, seeps, ponds, lakes, and wetlands, as well as shallow ground water.

5.5 "Wet season" shall mean that period of time from November through April of each year.

6.0 POLICIES:

6.1 It is the policy of King County to provide sewerage facilities adequate for the transportation, treatment, and disposal of industrial and other wastes and to operate the metropolitan sewerage system in such a manner that protects public health and the environment. In carrying out this policy, the objectives of this rule are:
6.1.1 To prevent pollutants from entering the sewerage system that will interfere with its normal operation, damage the collection or treatment systems, or contaminate the resulting biosolids;

6.1.2 To prevent the introduction of pollutants into the sewerage system that will not be adequately treated and will pass through into the environment;

6.1.3 To improve opportunities for recycling and reclamation of wastewater and biosolids;

6.1.4 To ensure protection of worker safety and health;

6.1.5 To implement waste reduction and recycling to prolong the useful life of existing and planned wastewater facilities and to protect the environment;

6.1.6 To focus sampling and inspection efforts on those industries discharging the greatest volume and concentration of pollutants while still recognizing the cumulative impact of small discharges;

6.1.7 To implement an enforcement response plan aimed at achieving compliance in the shortest time frame possible and promoting responsibility of the industrial user to be in compliance; and

6.1.8 To encourage persons conducting construction dewatering to contact the Department of Ecology to obtain authorization to discharge to the surface waters.

6.2 Applicable permit applications are available from King County Department of Natural Resources, Industrial Waste Section, 130 Nickerson, Suite 200, Seattle, Washington, 98109.

7.0 PROCEDURES:

Action By: Discharger

Action:

7.1 During the dry season, obtain all applicable discharge authorizations required by Ordinance No. 11034, codified at K.C.C. 28.84.

7.2 During the wet season:

7.2.1 For site construction dewatering at rates of less than 25,000 gallons per day (gpd), obtain all applicable discharge authorizations required by Ordinance No. 11034, codified at K.C.C. 28.84.060

7.2.2 For discharges that would exceed 25,000 gpd, demonstrate to King County's satisfaction that a surface water discharge authorization cannot be obtained due to site restrictions and/or regulatory restrictions enforced by State and federal agencies including but not limited to the Washington State Departments of Ecology (WSDOE), Natural Resources, and Fish and Wildlife, and the U.S. Environmental Protection Agency; or

7.2.3 Demonstrate to King County's satisfaction that discharge to state waters has been previously approved by WSDOE, but a King County discharge authorization is requested for emergency discharge only.

Action By: DNR

Action:

7.3 Allow the discharge of water from construction dewatering activities during the dry season, subject to the discharger obtaining authorization as described above, and subject to sewer fees and site specific discharge conditions.

Action By: Discharger

Action:

7.4 Prohibit the discharge of water from construction dewatering activities during the wet season, except as provided above, and subject to sewer fees and site specific discharge conditions.

8.0 RESPONSIBILITIES:

8.1 Dischargers of water from construction dewatering activities are responsible for obtaining discharge authorizations from King County prior to discharge.

8.2 Dischargers of water from construction dewatering acvtivities are responsible for ensuring that water discharged to the sewer system meets the requirement of K.C.C. 28.84.060 (Ordinance No. 11034).

8.3 The King County Department of Natural Resources, Industrial Waste Program, is responsible for the enforcement of this public rule.

9.0 APPENDICES:

None.