Water Quality
Resource Quality Section
Water Management Branch
MINISTRY OF ENVIRONMENT
Water quality objectives are prepared for specific bodies of fresh, estuarine and coastal marine surface waters of British Columbia as part of the Ministry of Environment, Lands and Parks' mandate to manage water quality. Objectives are prepared only for those waterbodies and water quality characteristics that may be affected by human activity now or in the near future.
How Objectives Are DeterminedWater quality objectives are based the BC approved and working criteria as well as national water quality guidelines. Water quality criteria and guidelines are safe limits of the physical, chemical, or biological characteristics of water, biota (plant and animal life) or sediment which protect water use. Objectives are established in British Columbia for waterbodies on a site-specific basis. They are derived from the criteria by considering local water quality, water uses, water movement, waste discharges, and socio-economic factors.
Water quality objectives are set to protect the most sensitive designated water use at a specific location. A designated water use is one that is protected in a given location and is one of the following:
Each objective for a location may be based on the protection of a different water use, depending on the uses that are most sensitive to the physical, chemical or biological characteristics affecting that waterbody.
How Objectives Are UsedWater quality objectives routinely provide policy direction for resource managers for the protection of water uses in specific waterbodies. Objectives guide the evaluation of water quality, the issuing of permits, licences and orders, and the management of fisheries and the province's land base. They also provide a reference against which the state of water quality in a particular waterbody can be checked, and help to determine whether basin-wide water quality studies should be initiated.
Water quality objectives are also a standard for assessing the Ministry's performance in protecting water uses. While water quality objectives have no legal standing and are not directly enforced, these objectives become legally enforceable when included as a requirement of a permit, licence, order, or regulation, such as the Forest Practices Code Act, Water Act regulations or Waste Management Act regulations.
Objectives and MonitoringWater quality objectives are established to protect all uses which may take place in a waterbody. Monitoring (sometimes called sampling) is undertaken to determine if all the designated water uses are being protected. The monitoring usually takes place at a critical time when a water quality specialist has determined that the water quality objectives may not be met. It is assumed that if all designated water uses are protected at the critical time, then they also will be protected at other times when the threat is less.
The monitoring usually takes place during a five week period, which allows the specialists to measure the worst, as well as the average condition in the water.
For some waterbodies, the monitoring period and frequency may vary, depending upon the nature of the problem, severity of threats to designated water uses, and the way the objectives are expressed (i.e., mean value, maximum value).
Tributaries entering the Fraser River from the north are not examined specifically, but their effect on Fraser River water quality is considered. Similarly, only waster discharges along the north shore discharging directly into the river are discussed. A more detailed examination of watercourses and waste discharges in the area to the north from the Fraser River will be undertaken when water quality assessments and objectives are prepared for the Coquitlam-Pitt and Harrison-Lillooet areas. A detailed technical appendix was prepared and forms the basis for the conclusions presented here.
The Fraser River flows westerly for Hope to Kanaka Creek and subsequently to its confluence with the Strait of Georgia. The reach from Hope to Chilliwack is about 55 km in length, as is the reach from Chilliwack to Kanaka Creek.
The area to the south from the river, to the International Boundary was also examined in detail. This area comprises several tributaries including Hope Slough (and its tributary Elk Creek), Chilliwack Creek (and its tributaries Luckakuck and Atchelitz Creeks), The Salmon River, Chilliwack River, Gifford Creek, Clayburn Creek, Nathan Creek, a small length of Silverhope Creek and Wahleach (Jones) Creek. As well, Bertrand and Fishtrap Creeks which flow in a southerly direction into the United States were examined. Urban centers in this area include Abbottsford, Aldergrove, Vedder Crossing, Sardis, Chilliwack and Hope.
Low flows on the Fraser River occur from January through mid-April. Freshet commence at approximately that time and peaks in the late June.
Several smaller tributaries are discussed in this document. Those for which historical mean annual flows are available include Silverhope Creek near Hope (14 m3/s), Jones (Wahleach) Creek (9.5 m3/s), Hope Slough (up to 2 m3/s), the Chilliwack River (70 m3/s), the Sumas River (3.5 m3/s) And the Salmon River (1.5 m3/s).
Extensive recreational use is made of water bodies in the Fraser-Delta area, including boating and angling in the Fraser River and canoeing, kayaking and angling in the Chilliwack River. Chilliwack sand Cultus Lakes are used extensively for recreation for beaches, angling, swimming and parks.
Very little consumptive use is made of Fraser River water. Only 51.8 dam3/year is licences to be withdrawn for irrigation and 4.5 m3/d for drinking water. However, extensive use of water from tributaries is made for irrigation. Annually, this amounts to 5.6 dam3 from Silverhope Creek, 749 dam3 from Hope Slough, 92.6 dam3 from Elk Creek, 125 dam3 from the Chilliwack River, 679 dam3 from Sumas River, 231 dam3 from the Salmon River, 326 dam3 from Chilliwack Creek, 324 dam3 from Atchelitz Creek, 390 dam3 from Luckakuck Creek, 438 dam3 from Clayburn Creek, 125 dam3 from Gifford Creek and 254 dam3 from Fishtrap Creek. Drinking water requirements amount to 2.3 m3/d from Cultus Lake, 9 m3/d from the Salmon River, 702 m3/d from Clayburn Creek, 30 m3/d from Gifford Creek and 6.8 m3/d from Nathan Creek.
Major discharges to the Fraser River of secondary treated domestic sewage occur from the Hope sewage treatment plant (STP), the Kent STP, the Chilliwack STP, the MSA (also known as James or Abbotsford) STP, the Aldergrove STP. Permitted discharge volumes are 6800 m3/d from the Hope STP after treatment in an aerated lagoon system, 2730 m3/d from the Kent STP after treatment in an extended aeration system, 12,700 m3/d from the Chilliwack STP after treatment in an activated sludge plant, 20,500 m3/d from the MSA STP after treatment in a physical-chemical plant and 4546 m3/d from the Aldergrove STP following treatment in an activated sludge plant. Raw sewage bypasses to the Fraser River can occur from the Kent STP and the Chilliwack STP, while bypasses from the Aldergrove STP enter Bertrand Creek.
Other major discharges are Cargill Grain, a hog raising operation which uses a combined anaerobic/aerated lagoon system prior to discharging 250 m3/d to an exfiltration basin and Trinity Junior College, which is located near the Salmon River. The College provides secondary treatment to domestic sewage in two aerated lagoons and is allowed to discharge 282 m3/d to the Salmon River from October through May 15. However, the sewage also exfiltrates to the river.
Changes have been noted downstream from sewage treatment plants in the Fraser River at Hope, Kent and Chilliwack. These changes, which could affect water use by a aquatic life and humans if they persisted throughout the river, were reflected in reduced dissolved oxygen and increased phosphorus, ammonia, organic nitrogen, suspended solids and fecal coliforms. Complete mixing of effluents and river water probably had not occurred where samples were collected since calculations have indicated that with complete mixing may require changes in treatment or changes to the outfall systems used at these treatment plants. Some possible options include extending existing outfalls and/or adding diffusers. Localized effects of discharges are not always well defined, requiring that further data be collected.
Impacts from cattle operations could be important during low flows in several tributaries. These include Hope Slough, Elk Creek and the Salmon River.
Elk Creek, a tributary to Hope Slough had some high iron and manganese levels relative to those recommended for drinking, high phosphorous and fecal coliform values and low dissolved oxygen levels. Use of the water for drinking and by aquatic life potentially could be affected.
The Sumas River, a tributary to the Vedder River, had good water quality except for phosphorus, fecal coliforms and asbestos. Although phosphorus values in its lower reaches were typical of low productivity streams, higher phosphorus values and likely higher productivity existed in its upper reaches. In addition, fecal coliform values were generally high throughout the Sumas River, exceeding working water quality criteria for primary contact recreation. Naturally occurring asbestos values in the river were higher than found in most other water in North America. These high levels have been associated with high metal-levels, as well as toxicity problems to plants in flooded areas where sediments had been deposited.
There were some notable water quality problems evident in both Atchelitz and Chilliwack Creeks. These problems were low dissolved oxygen values and high phosphorus and fecal coliform values, High phosphorus values may have promoted algal growths which in turn caused the wide ranges of dissolved oxygen values noted. Additional sampling of the creeks has been recommended to check these possibilities. Algal growths can cause taste and odour problems in drinking water, as well as lead to fluctuating dissolved oxygen levels which can stress aquatic life.
Both Cultus and Chilliwack Lakes are oligotrophic. Cultus Lake has been affected by Eurasian water milfoil (Myriophyllum spicatum) since 1977. Approximately 5 ha of an affected area 18.7 ha area is managed by rotavating or the installation of bottom barriers. The milfoil has spread into valuable shore-based sockeye spawning grounds at the south end of the lake.
The objectives can be considered as policy guidelines for resource managers to protect water uses in the specified water bodies. For example, they can be used to draw up waster management permits and plans, regulate water use of plan fisheries management. They can also provide a reference against which the state of water quality in a particular water body can be checked.
Water quality objectives have no legal standing and their direct enforcement would not be practical. This would be due to the difficulty of accurately measuring contaminants in receiving water and attributing the contamination exceeding the objective to particular sources for legal purposes and thus of proving violations and their causes. Hence, although water quality objectives should be used when determining effluent permit limits, they should not be incorporated as part of the conditions in a waste management permit.
Depending on the circumstances, water quality objectives may already be met in water body or may describe water quality conditions which can be met in the future. To limit the scope of the work, objectives are only being prepared for water bodies and for water quality characteristics which may be affected by man's activity now and in the foreseeable future.
Water uses including protection of aquatic life, wildlife, livestock and irrigation are designated for the Fraser River from Hope to Kanaka Creek, Hope Slough, Luckakuck Creek, Atchelitz Creek, Clayburn Creek and the Sumas River.
Use for drinking water supplies and protection of aquatic life, wildlife, livestock and irrigation are the designated uses for Elk Creek, Salmon River, Fishtrap Creek, Gifford Creek and Bertrand Creek. Designated water uses on Saar Creek are for protection of aquatic life, wildlife,, livestock and irrigation. Designated uses for Nathan Creek include drinking water, use by wildlife and protection of aquatic life.
Drinking water supply, primary contact recreation, protection of aquatic life, wildlife, livestock and irrigation are the designated water uses for the Chilliwack River and Cultus Lake. Chilliwack Lake has the same uses except livestock watering and irrigation. The protection of aquatic life and wildlife are the designated uses for Wahleach and a short length of Silverhope Creeks.
Various values are proposed as objectives for dissolved oxygen. These arise because the Fraser River is a migratory route, while its tributaries provide spawning and rearing habitat for salmonids. For these reasons, a minimum 7.75 mg/L level is proposed for the Fraser River, while three different objectives are proposed in spawning and rearing habitats, each objective being dependent upon the life cycle stage (e.g., egg, alevin or fry) of the affected fish.
Where treated sewage is discharged to the Fraser River, objectives have been proposed for pH, total chlorine residual, un-ionized nitrogen and fecal coliforms. The ph objective is proposed to help reduce the amount of un-ionized ammonia (and resulting toxicity) potentially present at any temperature. It also recognizes the sensitivity of the Fraser River to alkaline discharges. Total chlorine residual objectives are proposed to prevent toxicity in the receiving water, following chlorination to reduce fecal coliform concentration. Fecal coliform objectives are proposed to protect downstream water users. Toxicity due to un-ionized ammonia or chlorine residual has not been evident in the Fraser River.
Provisional objectives for fecal coliforms vary according to whether irrigation, recreation or drinking water is the most sensitive designated use. Thus objectives may appear as a geometric mean, a 90th percentile value or a maximum value, depending on water use and the degree of treatment required by the water user.
Objectives to protect the quality of Cultus and Chilliwack Lakes have been proposed to protect the value of these lakes. It has been recommended that no increased phosphorus loading should occur to Cultus Lake and that further development on Chilliwack Lake be subject to strict control due to the sensitivity of the lake and the long water-retention-time.
Should a development be proposed in the future for a sub-basin where provisional objectives do not exist for the characteristics of concern, the designated water uses should be protected while objectives are developed for those characteristics. Table 1 summarizes designated uses and provisional water quality objectives for water courses where these have been proposed.
| Water Bodies | Fraser River, Hope to Kanaka Creek | Hope Slough, Atchelitz, Luckakuck and Chilliwack Creeks | Elk and Bertrand Creeks, Salmon River | Sumas River |
| Designated uses | aquatic life, wildlife, livestock, irrigation | aquatic life, wildlife, livestock, irrigation | drinking water (complete treatment), aquatic life, wildlife, livestock, irrigation | aquatic life, wildlife, livestock, irrigation |
| fecal coliforms | less than or equal to 1000 MPN/100 mL geometric mean, 4000 MPN/100mL maximum, April to October | |||
| total chlorine residual | 0.002 mg/L maximum | not applicable | ||
| un-ionized ammonia-nitrogen | less than or equal to 0.007 mg/L average, 0.03 mg/L maximum | not applicable | ||
| total phosphorus | not applicable | |||
| dissolved oxygen | 7.75 mg/L minimum | 11.2 mg/L minimum when fish eggs are in "eyed" to hatch stages 8.0 mg/L minimum when fish eggs, larvae or alevin are present 6.0 mg/L minimum at all other times |
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| pH | 6.5 to 8.5 | not applicable | ||
| Water Bodies | Saar Creek | Chilliwack River | Cultus Lake | Chilliwack Lake |
| Designated uses | aquatic life, wildlife, livestock, irrigation | drinking water (partial treatment), aquatic life, wildlife, recreation, livestock, irrigation | drinking water (disinfection only), aquatic life, wildlife, recreation | drinking water (disinfection only), aquatic life, wildlife, recreation |
| fecal coliforms | less than or equal to 1000 MPN/100 mL geometric mean, 4000 MPN/100mL maximum, April to October | less than or equal to 100 MPN/100 mL 90th percentile | less than or equal to 10 MPN/100 mL 90th percentile near water intakes less than or equal to 200 MPN/100 mL geometric mean and less than or equal to 400 MPN/100 mL 90th percentile at bathing beaches |
not applicable |
| total chlorine residual | not applicable | |||
| un-ionized ammonia-nitrogen | not applicable | |||
| total phosphorus | not applicable | less than or equal to 0.01 mg/L average at spring overturn | not applicable | |
| dissolved oxygen | 11.2 mg/L minimum when fish eggs are in "eyed" to hatch stages 8.0 mg/L minimum when fish eggs, larvae or alevin are present 6.0 mg/L minimum at all other times |
11.2 mg/L minimum when fish eggs are in "eyed" to hatch stages 8.0 mg/L minimum when fish eggs, larvae or alevin are present 7.75 mg/L minimum at all other times |
5.0 mg/L minimum in hypolimnion | not applicable |
| Note: The objectives apply to discrete samples from all parts of the water body except from initial dilution zones of effluents. These excluded dilution zones are defined as extending up to 100 m downstream from the discharge point and no more than 50 percent across the width of the stream (25% in the case of the Fraser River), from the surface to the bottom. 1. Drinking water objectives (10, 100 and 1000-4000/100 mL) apply year round, the fecal coliform geometric mean, median and 90th percentile are calculated from at least 5 weekly samples taken in a period of 30 days. The recreation objective (200-400/100 mL) applies during the recreation season and the irrigation objective (1000-4000/100 mL) applies during the irrigation season. 2. Since the total chlorine residual objective is less than the minimum detectable concentration, it will be necessary to estimate the receiving water concentration using effluent loading and streamflow. The objective applies only if sewage effluent is chlorinated. 3. The average un-ionized ammonia is calculated from at least 5 weekly samples taken in a period of 30 days. 4. The average total phosphorus is calculated from a set of at least 3 samples taken at spring overturn, including near the surface, at mid-depth and near the bottom, all at mid-lake. 5. pH measurements can be made in-situ but must be confirmed in the laboratory if the objecxtive is exceeded. |
| Sites | Frequency and Timing | Characteristics to be Measured |
| Fraser River: u/s, d/s and sample of effluent from MSA STP, KENT STP, Aldergrove STP, Chilliwack STP, Cargill Grain | 1/month (December to April) for the first year 1/year (December to April) in subsequent years |
dissolved oxygen, pH, ammonia-nitrogen, total phosphorus, suspended solids, fecal coliforms, temperature, total chlorine residual |
| Salmon River: u/s and d/s from Trinity Junior College | 4 times (September and October) in the first year | dissolved oxygen, pH, ammonia-nitrogen, total phosphorus, temperature |
| Sumas River (site 0300030) Elk Creek (site 0300046) Saar Creekr (site 0300032) Chilliwack Creek (site 0300040) Luckakuck Creek (site 0300036) Atchelitz Creek (site 0920021) Hope Slough (site 0300141) |
3 times (December to April) in the first year once (May to November) in the first year |
dissolved oxygen |
| 5 times (July and August) annually | fecal coliforms | |
| Vedder Canal (site 0300033) | 5 times (August and September) yearly | dissolved oxygen, fecal coliforms |
| Cultus Lake | once between February 20 and March 10 yearly | total phosphorus |
| 5 times (July and August) annually | fecal coliforms, dissolved oxygen, chlorophyll-a | |
| Salmon River (site 0300023) and headwaters | 5 times at low flow and heavy rainfall for one year | total coliforms, fecal coliforms, fecal streptococci |
| Chilliwack Creek (site 0300040) and Atchelitz Creek (two sites) | monthly (May to Octember) for one year | dissolved oxygen, fecal coliforms |
| Saar Creek, Sumas River (two new sites), Hope Slough (two new sites), Elk Creek (two new sites) | 6 times (August and September) for one year | dissolved oxygen, orthophosphorus, ammonia and nitrate-nitrogen |
| Lonzo Creek u/s and d/s from Surrey Cooperative | 6 times for 1 year during rain events | dissolved oxygen, oil and grease |
| Lonzo Creek u/s and d/s from BCBC Hatchery | 6 times for 1 year | dissolved oxygen, orthophosphorus |
| Unnamed creek u/s and d/s from Bailey Road refuse (Sites 0301279 and 0301282) | twice a year at low flow for three years | dissolved iron, nitrite, fecal coliforms |
| Note: Sampling may need to be increased to check objectives, depending on circumstances. |
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