东营市河口区湖滨新区鸣翠湖景观设计MINGCUI LAKE LANDSCAPE DESIGN, LAKESIDE NEW ZONE, HEKOU DISTRICT, DONGYING

项目位置：中国山东省东营市

项目规模：97ha

设计公司：艾奕康环境规划设计（上海）有限公司

翻译：张旭

Location: Dongying, Shandong Province, China

Size: 97ha

Design Firm: AECOM Group

Translated by Zhang xu

该项目“海绵城市”的建设途径主要包括以下三方面。

对城市原有生态系统的保护

最大限度地保护原有的河流、湖泊、湿地等水生态敏感区，留有涵养水源充足、应对较大强度降雨的林地、草地、湖泊、湿地，维持城市开发前的自然水文特征，遵循“海绵城市”建设的基本要求。

生态恢复和修复

对已经受到破坏的水体和其他自然环境，运用生态手段进行恢复和修复，并维持一定比例的生态空间。

低影响开发

根据对城市生态环境影响最低的开发建设原则，合理控制开发强度，在场地中保留足够的生态用地，控制城市不透水面积比例，最大限度地减少对城市原有水生态环境的破坏，同时，根据需求适当开挖河湖沟渠，增加水域面积，促进雨水的积存、渗透和净化。

雨水径流管理根据鸣翠湖主要污染源分析，黄河引水和直接降雨的水质相对较优，而雨水径流水质可能受周边地块开发影响，对鸣翠湖水质造成一定影响。

对周边地块采取最佳雨水径流管理措施，如生态滤水带、雨水花园、绿色屋顶等，收集并处理路面、屋面、停车场以及其他不渗透表面的雨水径流，以改善径流水质，同时生态雨水管理设施有利于雨水下渗补给地下水，对长期改善土壤盐碱化有一定作用。

沿湖带雨水径流管理设计由于用地类型、场地情况的不同，对沿湖雨水径流管理进行分区治理，分别采取相应的生态雨水径流管理措施，以保护鸣翠湖的水质。水质主要分成以下三类。

（1）生态滤水带：大部分临湖区域结合景观设计生态滤水带，截留并处理周边地表雨水径流，经过植物根系以及滤料层净化后排入鸣翠湖，保护鸣翠湖水质的同时为鸣翠湖提供一定量的淡水资源。

（2）生态滤水带+雨水存储设施：部分区域由于场地标高的限制，排水入鸣翠湖存在一定难度，建议设置雨水存储设施，周边地表径流经生态滤水带处理后排雨水罐存储，之后可回用于周边绿化灌溉。

（3）湿地：鸣翠湖西岸用地以生态绿地为主，本身径流水质较优，同时湿地系统的设置为水质净化提供了保证。草桥沟汛期可能同时受强降雨以及风暴潮影响，排洪不畅，产生内涝问题，此时草桥沟水位急剧上涨，部分区域洪水位高达5m多，鸣翠湖紧邻草桥沟，因此与草桥沟之间的堤岸设置必须满足草桥沟防洪要求。

李陀水库（鸣翠湖）在草桥沟侧约8m的堤岸高程，约8m左右的堤岸足以抵挡草桥沟洪水，保证鸣翠湖不受草桥沟洪水的影响。鸣翠湖排涝纳入环城水系排涝体系，洪涝时启用强排泵，以确保排涝安全。排水口设计应确保鸣翠湖排水顺畅，可设置溢流坝进行控制，平时控制水位，当鸣翠湖水位超过3m时，溢流排水。为缓解区域的防洪排涝压力，建议鸣翠湖设计一定的蓄滞洪空间，湖区平均堤岸高程约4.5m，扣除0.5m的安全超高后，水位处于3～4m的空间均可作为滞洪空间。

综上，按50年一遇防洪排涝标准设计溢流坝尺寸：坝高3m，鸣翠湖水位高于3.0m时即开始溢流，宽不小于25m，与下游环城水系相连，以确保鸣翠湖湖体排涝安全。

The three main measures adopted in Sponge City Construction.

Protecting the existing urban ecological system

Maximizing the protection to the original sensitive aquatic zone, as rivers, lakes, wetland, etc., remaining sufficient water conservation area and the resilient forests, grassland, lakes, wetlands which can resist heavy storm. Maintaining the natural hydraulic features before city development, keep tight to the principles of sponge city construction.

Ecological restoration and repairmen

Applying ecological restore & repair method to the water bodies and other natural environment that had been damaged, maintaining a proper proportion of ecological space.

Low impact development

In accordance with the vision of development & construction with low impact on the ecological environment, controlling the development intensity properly, maintaining sufficient ecological land on site, limiting the ratio of the impervious area, minimizing the damage to the urban existing aquatic ecological environment. Meanwhile, excavating channels and lakes in line with reasonable demands, increasing the area of aquatic space, promoting the rainwater treatment process of retention, filtration and purification.

The stormwater runoff management is based on an analysis of the main pollutants' source in Cuiming Lake. The water drawn from Yellow River and the direct precipitation has better quality comparatively. However, been influenced by the development of the surrounding site parcels, the deteriorated runoff water would place a negative impact on water quality of Mingcui Lake.

Carrying on an optimal runoff management measure on the nearby site.

For instance, the ecological water treatment belt, rain garden, green roof. Collecting and disposing the runoff from the streets, roofs, parking places and other impervious areas, and purifying the runoff water quality. Meanwhile, the ecological stormwater management facilities along the lakeside could help to recharge ground water and ameliorate the saline soil condition in a long turn.

In the lakeside runoff management design, based on different types and distinct context of each site, the site was divided into different area. In this circumstances, the subarea management was implemented, specific design approach was apply to each area, in order to protect the water quality in Cuiming Lake.Three are there main categories for the water quality, shown as below.

(1). Ecological water treatment belt: in most of the lakeside area, the landscape design is integrate into the ecological water treatment belt, retaining and disposing the runoff from the surrounding area. And the purified runoff would be discharged into Cuiming Lake after flow through the plant'roots system and the filter material layer. It is not only protecting the water quality in the Cuiming Lake, but also serving as the source of certain amount of fresh water.

(2). Ecological water treatment belt & Storm water storage facilities: Due to the limitation of the site elevation, the runoff from some highland area is difficult to be discharged into Cuiming Lake. So a set of stormwater storage facility is supposed to be placed on the site. The runoff from the surrounding area would be collected in the storm water tank after flew through the water treatment belt, and the stored stormwater could be reused for the surrounding greenery irrigation.

(3). Wetland: the land on the west bank of Cuiming Lake is dominant by the ecological green space. For this reason, the original runoff was relatively clean, and the construction of the wetland system laid a profound base for the water purification. In the flood season, the straw bridge ditch would be influence by the heavy precipitation and storm tide, resulting in stagnation and waterlogging. In this period, the water level in straw bridge ditch elevated in a rapid rate, the flood water level in some area climaxed to 5 meters high. Cuiming Lake is just adjacent to Straw-Bridge ditch, therefore, the embankment between the Straw-Bridge ditch must satisfy the flood prevent requirement.

It is suggest to reserve the original embankment elevation of Lituo reservoir along the Straw-Bridge ditch, the proximately 8 meters embankment is higher enough to resist the flood from the ditch, making sure Mingcui Lake could be free from the floods'negative influence. Cuiming Lake is an impartible and organic part of the round-city flood drainage system. The potent discharge pump would be used during the flood period to ensure the drainage security. Constructing the overflow weir, controlling the water level in the common day and installing the outlet port to avoid the impeded drainage. When the water level surpassed 3 meters, the storm water would be overflow. In order to relieve the flood drainage stress, the design team prepared some flood retention & detention space the Cuiming Lake. The average water level in Cuiming Lake is proximately 4.5 meters, deduct the reserved 0.5 meters for the security concern, the fluctuated water level ranges from 3 meters to 4 meters, the space between this two elevations could conserve the flood.

In general, the size and dimension in the design is accord with the controlling and drainage standards of the once 50 years rain. The height of the dam is 3 meters high, the lake water would overflow when the water level surpass 3.0 meters, the breadth of overflow paths is no less than 25 meters, and connected with the round city river system in the downstream, ensuring the flood drainage security of Cuiming Lake body.