CHAPTER 4-9 HYDRAULICS PROJECT PERMITTING
1. The Confederated Tribes of the Colville Reservation has a primary interest in the protection of its fish and wildlife resources within and influenced by the waters of the Colville Reservation. Fish and wildlife have traditionally been important resources both as a food source and spiritually to the Tribes.
2. Human activities affecting the bed stream and or wetlands have a potential impact on fish life and certain wildlife species and shall be regulated to protect and maintain the high quality of waters necessary to protect fish and wildlife. The economy, health, safety, and welfare of the people residing and doing business on the Colville Indian Reservation may also be adversely affected by activities within the waters of the Reservation by both Indian and non-Indian people whether on trust or fee land. Inadequate control of such activities can contaminate and degrade surface and groundwater, destroy fish and wildlife habitat resources.
3. The Confederated Tribes of the Colville Reservation has jurisdiction to enforce the tribal hydraulics project permit system in order to protect fish and wildlife and the waters of the Reservation.
4-9-2 Territory Covered.
The provisions of this Chapter, known as the Hydraulics Project Permit Chapter of the Colville Law and Order Code, shall apply to all surface waters of the Colville Indian Reservation. Every human activity taking place in the waters of the Colville Indian Reservation which may affect the quality of these surface waters and thereby having a possible effect on fish and wildlife shall be subject to the provisions of this Chapter.
This Chapter is enacted by the Colville Business Council pursuant tot he authority vested in it by Article V, Section 1 (a) of the Constitution of the Confederated Tribes and its general duty and authority to secure the political integrity; to protect and preserve the tribal property, wildlife and natural resources; to cultivate and preserve Indian culture; to protect the health, security and general welfare; and, to enhance the economic security of the Confederated Tribes, as well as protecting the interests of all those found, or owning property on the Colville Indian Reservation.
1. The Department of Fish & Wildlife of the Colville Confederated Tribes shall administer this Chapter. From time to time, and as it deems appropriate, the Department may recommend that the Colville Business Council amend this Chapter. The Department of Fish & Wildlife may propose that the Business Council adopt a fee schedule for the purpose of establishing fees which may be charged for permits and other administrative services provided by the Department under this Chapter.
2. The Department is authorized and empowered to adopt such rules, regulations and forms as it deems necessary to implement the objectives and purposes of this Chapter. Such rules and regulations shall be subject to review and approval by the Business Council and shall comply with the requirements of the Colville Administrative Procedures Act.
3. The Department may temporarily suspend the application of this Chapter for an emergency hydraulic project necessitated by fire or emergency other than set forth in section 4-9-13. Provided, that the person engaging in such a project shall have a duty to mitigate any damage or loss of any fishery or water dependent wildlife resource and costs of rehabilitation resulting from such project.
Unless otherwise required by its context, as used in this Chapter:
4-9-6 Hydraulic Approval Permit Application.
1. Any person or governmental agency who desires to construct any form of hydraulic project or perform other work that will use, divert, obstruct or change the natural flow or bed of any waters of the Colville Reservation shall, before commencing construction or work thereon and to ensure the proper protection of fish and wildlife secure written approval from the Colville Department of Fish & Wildlife as to the adequacy of the measures proposed to be used for the protection of fish and wildlife.
2. A complete application for approval shall contain general plans for the overall project, complete plans and specifications of the proposed construction or work within the ordinary high water mark and complete plans and specifications for the proper protection of fish and wildlife. Discrete projects involving more than one instance of construction below the ordinary high water mark such as forest harvest activities, mining activities or road construction require only one application package.
3. The Department shall grant or deny approval within sixty (60) calendar days of the Department's receipt of the completed application and notice of compliance with any other applicable requirement of the laws of the Colville Confederated Tribes for the protection of water quality.
4-9-7 Denial of Approval.
1. Protection of fish and wildlife and attributes of the aquatic and/or wetland environment required to support fish and wildlife shall be the only grounds on which approval may be denied or conditioned.
2. If approval is denied, the Department shall provide the applicant a written statement of the specific reason why and how the proposed project would adversely affect fish and wildlife.
4-9-8 Use of Permits.
1. Approval of a project is valid for a period of up to five (5) years as specified in any permit issued by the Department.
2. An approval for projects that divert water for agricultural irrigation or stock watering purposes and that involves seasonal construction or other work shall remain in effect without a need for periodic renewal. The permittee must notify the Department before commencing the construction or other work within the area covered by the approval.
3. The permittee must commence construction within the time specified on the permit and demonstrate substantial progress on construction of that portion of the project relating to the approval within two (2) years of the date of issuance. Lack of substantial progress may constitute a violation of the terms of the permit. Uncompleted projects may be deemed public safety hazards, declared a nuisance and abated as such or the Department may order them removed and/or mitigated by the permittee.
4-9-9 Modification of Permit.
1. The Department may, after consultation with the permittee, modify an approval due to changed conditions. The modification shall become effective unless appealed as set forth in paragraph 4-9-11 within thirty (30) days from the notice of the proposed modification. The burden is on the Department to show that changed conditions warrant the modification in order to protect fish and wildlife.
2. A permittee may request modification of an approval due to changed conditions. The request shall be processed within forty-five (45) calendar days of receipt of the written request. A decision by the Department may be appealed to the CEQC pursuant to paragraph 4-9-11. The burden is on the permittee to show that changed conditions warrant the requested modification and that such modification will not impair fish and wildlife.
4-9-10 Violations, Enforcement, and Civil Penalties.
1. Any person or government agency who commences construction on any hydraulic works or project subject to this Chapter without first having obtained written approval of the Colville Department of Fish & Wildlife as to the adequacy of the means proposed for the protection of fish and wildlife, or any person or government agency who fails to follow or carry out any of the requirements or conditions as are made part of such approval, is subject to a civil penalty of up to $1000.00 per day for said violation.
2. If the Department determines that a person has violated a provision of this Chapter or any condition of an approved permit, it shall immediately issue a notice in writing describing the nature of the violation (including the amount of any civil penalty imposed) and serve the notice either by certified mail or personally on the alleged violator.
3. Any person incurring any penalty under this Subchapter may appeal the same to the CEQC as set forth in paragraph 4-9-11. An appeal shall be filed within ten (10) days after receipt of a notice imposing any penalty. The penalty imposed shall become due and payable ten (10) days after receipt of the notice imposing the penalty unless an appeal is filed. Whenever an appeal of any penalty incurred under this Subchapter is filed, the penalty shall become due and payable only upon completion of all review proceedings and the issuance of a final order confirming the penalty in whole or in part.
4. If a civil penalty is imposed pursuant to the provisions of this section and the person incurring the penalty continues construction of any such works or projects without fully complying with the provisions hereof, such works or projects are hereby declared a public nuisance and shall be subject to abatement as such.
5. If the amount of any penalty is not paid within thirty (30) days after it becomes due and payable, the Office of the Reservation Attorney, upon the request of the Director of the Colville Department of Fish & Wildlife shall bring an action in the name of the Confederated Tribes of the Colville Reservation in the Colville Tribal Court to recover such penalty.
6. Any person or governmental entity commencing construction on any hydraulic project or work without a permit as required by this Chapter or in violation of any term of any permit issued pursuant to this Chapter shall be liable in a civil action brought by the Colville Confederated Tribes in the Colville Tribal Court for damage to or loss of any fishery or water dependent wildlife resource and costs of rehabilitation, restoration, monitoring, investigation, laboratory and any other fees and analysis along with attorney fees.
1. Any issuance, denial, conditioning or modification of a hydraulics approval shall be appealable to the Colville Environmental Quality Commission within ten (10) days of the notice of decision by the Department. The CEQC shall affirm, reverse or amend the decision by the Department based on the same standards as set forth in Section 4-9-7 of this Chapter. The burden shall be upon the Department to show that the denial or conditioning of any approval is solely aimed at the protection of fish and wildlife.
2. The CEQC shall make its decision within thirty (30) calendar days after it receives written notice of a timely administrative appeal, provided that the CEQC may reasonably extend the time for decision with the consent of the parties to the appeal or upon finding of fact that such an extension is necessary for the proper consideration of the appeal.
3. Any appeal filed pursuant to this section shall follow the procedures for contested cases under 2-4-12 through 2-4-18 of the Colville Administrative Procedure Act.
4-9-12 Judicial Review.
The decision of the CEQC is subject to judicial review in conformity with the Colville Administrative Procedure Act, Chapter 2-4 of the Colville Tribal Code (C.T.C. 2-4-19).
4-9-13 Emergency Response.
In the case of an emergency arising from weather or stream flow conditions or other natural conditions, the Department shall immediately upon request issue oral approval for removing any obstruction, repairing existing structures, restoring stream banks, or to protect property threatened by the stream or a change in the stream flow without the necessity of obtaining a written approval prior to commencing work. Conditions of an oral approval shall be reduced to writing within thirty (30) days and complied with as otherwise provided for in this Chapter.
4-9-14 Notice of Permit to Divert or Store Water.
It is the policy of the Colville Business Council that a flow of water sufficient to support game fish and food fish populations as well as wetland dependent wildlife species populations be maintained at all times within the waters of the Colville Reservation. The Tribes' Water Administrator shall give the Director of the Department of Fish & Wildlife notice of each application for a permit to divert or store water. The Director of Fish & Wildlife shall have thirty (30) days after receiving the notice to state his objection to the application. The permit shall not be issued until the thirty (30) day period has elapsed. The Tribes' Water Administrator may refuse to issue a permit if, in the opinion of the Director of Fish & Wildlife, issuing the permit might result in lowering the flow of water in a stream below the flow necessary to adequately support food fish and game fish populations in the stream or lowering level of water within a wetland below that level necessary to provide suitable habitat for dependent wildlife species.
4-9-15 Federal Laws and Trust Responsibility Not Modified.
Nothing in this Chapter now or as hereafter amended shall either modify or waive any requirement to comply with applicable federal laws and regulations, or be construed to modify, waive or impair the trust responsibility of the United States.
If any provision of this Chapter, or the application thereof, to any person or circumstances is held invalid, such invalidity shall not affect other provisions or application of this Chapter which can be given effect without the invalid provision or application, and to this end, the provisions of this Chapter are declared to be severable.
4-9-50 Bank Protection and Fill Placement.
The following technical provisions shall apply to bank protection or fill placement projects; unless otherwise excepted by the Department:
1. Bank protection or fill placement work shall be confined to damaged banks.
2. Watercourse encroachment shall be held to a minimum.
3. Bank protection or fill material shall not appreciably reduce normal watercourse capacity or configuration.
4. The toe shall be designed to protect the integrity of bank protection material.
5. Bank sloping shall be accomplished in a manner that will prevent the release of overburden material into the water.
6. Bank protection material shall be clean, angular rock or other material of a sufficient size to prevent its being washed away by water action. River gravel shall not be used as exterior armor.
7. Bank protection and filter blanket material shall be placed from the bank or a barge. Dumping onto the bank face shall be permitted only if the toe is established and the material can be confined to the bank face.
8. Filter blanket material shall be place prior to placement of bank protection material.
9. Alteration or disturbance of the bank and bank vegetation shall be held to a minimum.
10. Overburden material resulting from this project shall be deposited outside of the streamside management zone (see CTC 4-7-3(zz)) and stabilized so as not to reenter the water.
11. Bulkheads shall be constructed in the dry.
12. Bulkhead faces shall be constructed of material not readily subject to erosion.
13. Equipment other than hand tools shall not enter the water except as specified in the permit.
4-9-51 Bridge, Pier, and Piling Construction.
The following technical provisions shall apply to bridge, pier, and piling construction projects; unless otherwise excepted by the Department.
1. Excavation for the footings, piers, or abutments shall be isolated from the wetted perimeter by a dike, cofferdam, or similar mechanism.
2. Waste water discharged to receiving waters shall not adversely impact fish life.
3. Structures containing concrete or wood preservatives shall be cured or dried prior to water encroachment.
4. Abutments, piers, piling, sills, etc., shall not restrict the flow so as to cause any appreciable increase in backwater elevation or scour and shall be aligned to cause the lease effect on the hydraulics of the body of water.
5. Riprap materials used for structure protection shall be clean and of sufficient size to prevent their being washed away.
6. Backfilling and armoring around each structure shall take place prior to removal of cofferdams.
7. The bridge shall be constructed high enough to pass the fifty-year flood level. Exception shall be granted if applicant provides design criteria to support a more appropriate level.
8. Alteration or disturbance of bank or bank vegetation shall be held to a minimum, and all disturbed areas shall be protected from erosion and revegetated.
9. Anchoring systems for floating structures shall be designed and deployed in a manner that will not damage the beds as a result of structure or anchor movement.
4-9-52 Bridge Construction--Stringer Type.
The following technical provisions shall apply to bridge construction--String type projects; unless otherwise excepted by the Department:
1. Unless construction is separated from tribal waters by use of a cofferdam or similar mechanism, excavation for and placement of the foundation and superstructure shall be outside the ordinary high water line.
2. At least one end of the bridge or stringer shall be securely anchored.
3. The stringers or structure shall be placed by floating equipment or by working from outside the ordinary high water line and in a manner as to not damage the beds or banks.
4. Alteration or disturbance of bank or bank vegetation shall be held to a minimum and all disturbed areas shall be revegetated or otherwise protected form erosion.
5. Removal of existing or temporary structure shall be accomplished so that the structure and associated materials does not enter the watercourse and placed so it will not reenter the watercourse.
6. The bridge shall be constructed high enough to pass the fifty-year flood level. Exception shall be granted if applicant provides design criteria to support a more appropriate level.
4-9-53 Channel Change--Temporary and Permanent.
The following technical provisions shall apply to channel change--Temporary and permanent projects: unless otherwise excepted by the Department:
1. Permanent new channels shall be similar in length, width, depth, gradient, and meander configuration as the old channel.
2. The new channel shall provide fish habitat similar to that which previously existed in the old channel.
3. During construction, the new channel shall isolated from the flowing stream by plugs at the upstream and downstream ends of the new channel.
4. Diversion of flow into a new channel shall be accomplished by;
5. Filling of the old channel shall begin from the upstream closure and the fill materials shall be compacted. Water discharging form the fill shall not adversely impact fish life.
6. Before water is diverted into a permanent new channel, the bank shall be armored to prevent erosion.
7. The angle of the structure used to divert the water into the new channel shall allow a smooth transition of water flow.
8. After completion of the permanent new channel and filling of the old channel, all unprotected banks shall be revegetated or otherwise protected to prevent erosion.
9. The applicant shall have fish capture and transportation equipment ready and on the job site. Captured fish shall be immediately and safely transferred to free flowing water.
4-9-54 Channel Realignment.
The following technical provisions shall apply to channel realignment projects; unless otherwise excepted by the Department:
1. The realigned channel shall provide fish habitat similar to that which previously existed.
2. All material removal from the new channel shall take place before any filling operations within the existing channel. Materials removal shall proceed from midstream toward the bank and be completed prior to filling.
3. Excavation and filling may take place simultaneously if excavated materials are to be used in the filling operation.
4. Prior to filling, an armored dike or other approved mechanism shall be constructed to divert the flowing stream and isolate the file area.
5. Filling shall begin at the upstream end and proceed downstream.
6. Water discharging from the fill area shall not adversely impact fish life.
7. The applicant shall have fish capture and transportation equipment ready and on the job site. Captured fish shall immediately be transferred safely to free flowing water.
4-9-55 Conduit Crossing.
The following technical provisions shall apply to conduit crossing projects; unless otherwise excepted by the Department;
1. Conduit alignment shall be as nearly perpendicular to the watercourse as possible.
2. The conduit shall be installed at sufficient depth so that subsequent disturbance of the bed of the watercourse is avoided.
3. Boring or jacking:
4. Trench excavation:
5. Trenches shall be backfilled with approved with approved materials and the bed shall be returned to pre-project condition.
6. Excess spoils shall be disposed of so as not to reenter the watercourse.
7. The conduit approach trench shall be isolated from the watercourse until laying of the conduit across the watercourse taken place.
8. Alteration or disturbance of banks or bank vegetation shall be held to a minimum and all denuded areas shall be revegetated or otherwise protected from erosion.
4-9-56 Culvert Installation.
The following technical provisions shall apply to culvert installation projects; unless otherwise excepted by the Department:
1. All permanent culverts together with their water crossing statement shall be capable of handling the fifty (50) year flood.
2. Permanent culverts too small to conduct fifty (50) year floods may be installed if they are armored to a sufficient extent to allow flood waters to flow over the crossing without significant erosion occurring. This design must be approved by the Department of Environmental Trust.
3. Minimum sizes of permanent culverts are:
4. Culverts constructed for permanent stream crossings should be of galvanized steel, concrete, aluminum or plastic and of sufficient gauge or thickness. Two feet or half the diameter of the culvert, whichever is greater, shall be the minimum overburden.
5. The alignment and slope of the culvert shall conform to the natural flow of the stream for all streams. Culverts shall be designed and constructed so as not to impede fish passage.
6. In areas where fish are present, the bottom of the culvert shall be installed slightly below the natural stream bottom at both ends of the culvert.
7. All culvert installations shall terminate on materials that will not erode under full flow of the culvert.
8. Culvert approaches shall be hand-cleared of natural and man-made debris for a distance of one hundred (100) feet upstream from the culvert inlet of all material that may reasonable be expected to plug the culvert.
9. The inlet ends of all ditch culverts shall have adequate catch basins and head walls to minimize the risks of culvert siltation and "by-pass" of the culvert from erosion of the head wall. Rock headwalls shall be placed on all culverts where annual peak flows exceed 100 cfs; and where headwall erosion is expected on smaller streams, as determined by the Department.
10. Ditch culverts that may reasonably be expected to carry near capacity water volumes or to encounter some siltation should:
11. Fill around culverts shall be compacted during placement to avoid failure by undercutting and stream bed excavation should be avoided.
12. All required culverts, ditches, cross drains, drainage dips, water bars and diversion ditches shall be installed concurrently with construction of the roadway.
4-9-57 Temporary Bypass Culvert or Flume.
The following technical provisions shall apply to temporary bypass culvert or flume projects; unless otherwise excepted by the Department:
1. The temporary bypass culvert or flume shall be in place prior to initiation of other work in the wetted perimeter.
2. A sandbag revetment or similar device shall be installed at the inlet to divert the entire flow through the culvert or flume.
3. A sandbag revetment or similar device shall be installed at the downstream end of the culvert or flume to prevent backwater from entering the work area.
4. Culvert or flume shall be of sufficient size to pass flows and debris occurring during the project.
5. Prior to releasing the water flow to the project area, all bank protection or armoring shall be completed.
6. Upon completion of the project, all material used in the temporary bypass shall be removed from the site and the site returned to pre-project conditions.
4-9-58 Temporary Water Crossings.
The following technical provisions shall apply to temporary water crossings; unless otherwise excepted by the Department:
1. "Fording" or limited crossings that utilize the natural stream bed as a road may be conditionally permitted through approval of specific crossings site location(s), frequency and dates of occurrence.
2. Temporary bridges or culverts, adequate to carry the twenty-five (25) year flow for the operation period can be used when:
The fllowing technical provisions shall apply to dredging projects; unless otherwise excepted by the Department:
1. Dredging shall not be conducted in fish spawning areas, or within waterfowl nesting areas.
2. During the dredging of a lake or pond, a boom or similar device shall be installed to contain floatable materials.
3. Dredged bed materials shall be disposed of at a site specified by the Department.
4. Dredging shall be conducted with dredge types that cause the lowest mortality on fish life.
5. Dredging shall stop when distressed or dead fish are observed in the work area. The Department shall be notified immediately.
6. If a hydraulic dredge is used, it shall be operated with the intake on or below the surface of the material being removed. Reverse purging of the intake line shall be held to a minimum.
7. If a drag line or clamshell is used, it shall be operated to minimize turbidity. During excavation, each pass with the clamshell or drag line bucket shall be complete. Dredged material shall not be stockpiled in the water.
8. Upon completion of the dredging the watercourse bed shall not contain pits, potholes, or large depressions.
4-9-60 Gravel Removal.
The following technical provisions shall apply to gravel removal projects; unless otherwise excepted by the Department:
1. Pre-project and post project monitoring of gravel recruitment and other related physical parameters is required for commercial and large scale flood control projects.
2. An excavation line shall be established. "Excavation line" means a line on the dry bed, parallel to the water's edge: two feet vertically above the existing water level, and changes with water level fluctuations.
3. Bed material shall not be removed from the water side of the excavation line.
4. Excavation shall being at the excavation line and proceed toward the bank, perpendicular to the alignment of the watercourse.
5. The maximum distance of excavation toward the bank from the excavation line shall be approximately equal throughout the excavation zone. "Excavation zone" means the area between the excavation line and the bank.
6. The excavation zone shall be identified by boundary markers.
7. A minimum two percent gradient upward from the excavation line shall be maintained in the excavation zone.
8. At the end of each day's operation the excavation zone shall not contain pits or potholes.
9. Excavated materials shall not be stockpiled or spoiled within the ordinary high water line.
10. Equipment shall not enter the wetted perimeter of the watercourse.
11. Debris in the excavation zone shall be disposed of so as not to reenter the watercourse.
12. Gravel washing or crushing operations shall not take place below the ordinary high water line.
13. Gravel removal may require a permit from the Tribal Geology Department.
4-9-61 Log and Log Jam Removal.
The following technical provisions shall apply to log and log jam projects; unless otherwise excepted by the Department:
1. Logs and log jams shall be removed by yarding from the bank.
2. Where logs are to be yarded up a bank, skid logs shall or similar methods shall be used to prevent bank damage.
3. Upon completion of the yarding operation skid logs shall be removed and the bank restored to pre-project condition.
4. Material associated with the log or debris jam shall be removed and disposed of so as not to reenter the watercourse.
5. Logs embedded in a bank or bed shall be cut off at the bank or bed line.
6. Log or debris jam removal shall be accomplished in a manner which prevents the release of logs or debris downstream.
7. Depressions created in gravel bars shall be filled, smoothed over, and sloped toward the water.
The following technical provisions shall apply to logging projects; unless otherwise excepted by the Department:
1. Trees shall not be felled into or across a watercourse.
2. Logs transported across a watercourse shall be suspended so no portion of the logs or limbs can enter the watercourse or damage the bed and banks.
3. Debris resulting from the project shall be removed from the bed during the operation and before removal of equipment from the site. Debris removal shall be accomplished so the watercourse, bed or banks are not disturbed.
4-9-63 Outfall Structures.
The following technical provisions shall apply to outfall structure projects; unless otherwise excepted by the Department:
1. The outfall structure shall not be designed and constructed to prevent the entry of fish.
2. The watercourse bank and bed at the point of discharge shall be armored to prevent scouring.
3. Excavation for placement of the structure or armoring materials shall be isolated from the wetted perimeter.
4. Alteration or disturbance of banks or bank vegetation shall be held to a minimum, and all disturbed areas shall be revegetated or otherwise protected from erosion.
5. Structures containing concrete or wood preservatives shall be cured prior to water encroachment.
4-9-64 Pond Construction.
The following technical provisions shall apply to pond construction projects; unless otherwise excepted by the Department:
1. Ponds shall not be constructed within the watercourse.
2. Ponds shall be designed and constructed to prevent the entry of fish.
3. Flow from the pond to the watercourse shall be by gravity. Pond return flow shall be located near the inlet.
4. Initial filling of the pond shall occur during a high flow period. Fifty percent of the flow shall be maintained within the watercourse during initial filling of the pond.
5. The work area shall be isolated from the watercourse during construction of the pond, the diversion system, and the return flow system.
6. Prior to the initial filling, all disturbed banks shall be revegetated or other wise protected to prevent erosion.
7. Ponds shall be designed and constructed so the outflow temperature is not harmful to fish life.
4-9-65 Water Diversions--General Fish Screening Criteria.
The following technical provisions may apply to water diversions where fish screens are required. General fish screening criteria are applicable to rotary drum screens, traveling screens, belt screens and stationary flat plat screens.
Screens shall be designed, constructed and located as follows:
1. Structure placement - (flowing waters river and creeks):
2. Structure placement-nonflowing waters (lakes and reservoirs): In nonflowing waters, diversion structures and associated fish screens will be constructed offshore to minimize fish contact.
3. Approach velocity (local velocity component perpendicular to the screen face) shall not exceed:
4. Wetted screen area, excluding area blocked to flow by structure components, required at ordinary low water shall be calculated by dividing maximum diverted flow by the allowable approach velocity.
5. In flowing water, the velocity component parallel and adjacent to the screen face shall be at least two times the approach velocity. Screen faces shall be placed flush with adjacent screen bay piers or walls.
6. Screen openings shall not exceed 1/4 (0.25) inch measured horizontally. Where fish less than 60mm in length are present the screen openings shall not exceed 3/32 (0.09375) inch.
7. The long axis of slot or rectangular screen openings shall be vertical.
8. Screens may be constructed of any rigid material, woven or perforated, that physically excludes fish provided that structural integrity and cleaning effectiveness are not impaired.
9. Screens shall be removed only by written permission of the Department.
10. Alteration or disturbance of banks or bank vegetation shall be held to a minimum, and all disturbed slopes shall be revegetated or otherwise protected from erosion.